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Friday, May 30, 2025

Spiral of silence

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Spiral_of_silence
Spiral of silence illustrated

The spiral of silence theory is a political science and mass communication theory which states that an individual's perception of the distribution of public opinion influences that individual's willingness to express their own opinions. Also known as the theory of public opinion, the spiral of silence theory claims individuals will be more confident and outward with their opinion when they notice that their personal opinion is shared throughout a group. But if the individual notices that their opinion is unpopular with the group, they will be more inclined to be reserved and remain silent. In other words, from the individual's perspective, "not isolating themself is more important than their own judgement", meaning their perception of how others in the group perceive them is more important to themself than the need for their opinion to be heard.

According to Glynn (1995), "the major components of the spiral of silence include (1) an issue of public interest; (2) divisiveness on the issue; (3) a quasi-statistical sense that helps an individual perceive the climate of opinion as well as estimate the majority and minority opinion; (4) 'fear of isolation' from social interaction "(though, whether this is a causal factor in the willingness to speak out is contested)"; (5) an individual's belief that a minority (or 'different') opinion isolates oneself from others; and (6) a 'hardcore' group of people whose opinions are unaffected by others' opinions."

The theory is not without criticism, some arguing that its widely understood definition and parameters have not been updated to reflect the behavior of 21st century society. Others point out that there is no room within the theory to account for variables of influence other than social isolation.

Background

In 1974, Elisabeth Noelle-Neumann, a German political scientist, created the model called "Spiral of Silence". She believed that an "individuals willingness to express his or her opinion was a function of how he or she perceived public opinion." In 1974, Neumann and her husband founded the "Public Opinion Organization" in Germany. She was also the President of the "World Association for Public Opinion Research" from 1978 to 1980.

Noelle-Neumann evolved the spiral of silence theory from research on the 1965 West German federal election. The research, according to Noelle-Neumann, "measured a lot more than we understood." The two major parties were locked in a dead heat from December until September, with a series of questions of public perception of the election winner was showing steady, independent movement. During the final days of the election, 3 to 4% of the voters shifted in the direction of the public's perception of the winner. A similar shift happened in the 1972 election, which began the development of the spiral of silence as a theory of public opinion.

According to Shelly Neill, "Introduced in 1974, the Spiral of Silence Theory [...] explores hypotheses to determine why some groups remain silent while others are more vocal in forums of public disclosure." The spiral of silence theory suggests that "people who have believed that they hold a minority viewpoint on a public issue will remain in the background where their communication will be restrained; those who believe that they hold a majority viewpoint will be more encouraged to speak." The spiral of silence theory arose from a combination of high public uncertainty about a topic with an increase in the flow of communication.

The theory explains the formation of social norms at both the micro and macro level. "As a micro-theory, the spiral of silence examines opinion expression, controlling for people's predispositions – such as fear of isolation, and also demographic variables that have been shown to influence people's willingness to publicly express opinions on issues, such as agricultural biotechnology." This micro effect is seen in experiments such as the Asch conformity experiments, conducted as early as the 1950s, in which a group of students are asked to compare the length of lines. All but one student are coached ahead of time on what answers to give and how to behave. When the coached subjects gave unanimously incorrect answers, the dissenter tended to agree with the majority, at times even when the difference between the lines was so egregious as seven inches. On the macro level, the spiral of silence occurs if more and more members of the perceived minority fall silent. This is when public perceptions of the opinion climate begin to shift. "In other words, a person's individual reluctance to express his or her opinion, simply based on perceptions of what everyone else thinks, has important implications at the social level." As one opinion gains interest, the amount of exposure it receives increases, leading the public to believe it is the majority. The perceived minority then faces the threat and fear of isolation from society unless they conform. As the opinion gains momentum, the perceived minority falls deeper into their silence. This continues until the perceived minority no longer speaks out against it, either by presenting an image of agreement or actually conforming, and the opinion of the perceived majority ultimately becomes a social norm. Large scale effects of the spiral of silence can be seen when examining the growth of the dominant opinion within a countries political climate or other such issues.

The spiral of silence has continued to be observed and studied since then. In today's world, technology can play a key part in the spiral of silence, something that could not have been predicted at the time of its inception. For example, survey data showed that during the 2016 US presidential election, opinion congruency for democratic candidate Hillary Clinton in society at large and for republican candidate Donald Trump on Facebook had indirect associations for willingness to present one's opinion both offline and online.

Spiral model

The spiral model is used to visually represent the theory. It claims that an individual is more likely to go down the spiral if his or her opinion does not conform with the perceived majority opinion. The following steps summarize how the process works:

  1. The model begins with individuals' inherent desire to blend with society. The fear of social isolation is necessary for the spiral to occur.
  2. Individuals who notice that their personal opinion is spreading will voice this opinion confidently in public. On the other hand, individuals who notice that their opinions are losing ground will be inclined to adopt a more reserved attitude when expressing their opinions in public.
  3. Representatives of the spreading opinion talk quite a lot while the representatives of the second opinion remain silent. An opinion that is being reinforced in this way appears stronger than it is, while a suppressed opinion will seem weaker than it is.
  4. The result is a spiral process which prompts other individuals to perceive the changes in opinion and follow suit until one opinion becomes established as the prevailing attitude. Meanwhile, the other opinion is pushed back and rejected by most. The end of the spiral refers to the number of people who are not publicly expressing their opinions, due to the fear of isolation.

In summary, the spiral model is a process of formation, change, and reinforcement of public opinion. The tendency of the one to speak up and the other to be silent begins a spiraling process which increasingly establishes one opinion as the dominant one.

Furthermore, Noelle-Neumann describes the spiral of silence as a dynamic process, in which predictions about public opinion become fact as mass media's coverage of the majority opinion becomes the status quo, and the minority becomes less likely to speak out.

Relationship with other kinds of social influence

The basic ideas for the spiral of silence are not unique and are closely related to theories on conformity. In 1987, Kerr, MacCoun, Hansen and Hymes introduced the idea of the "momentum effect". The momentum effect states that if some members of a group move toward a particular opinion, others will follow. Others have described similar "gain-loss effect" (Aronson & Linder, 1965), and "bandwagon effect" (Myers & Lamm, 1976). Experiments also show how the spiral of silence and the bandwagon effect jointly undermine minority positions when pre-election polls are shown to voters.

Epistemology

Public

Scholars have misguided interpretations of "public opinion", confusing it with government and therefore limiting the understanding of the term as it relates to the theory. Noelle-Neumann clarifies this by creating three distinct meanings of "public." First, is the legal term used to define "public land" or "public spaces." Second concerns the issues of people as seen in journalism. Finally, public as in "public eye" is used in social psychology and refers to the way people think outwardly about their relationships. Public, in this sense, could be characterized as social psychology. This is the meaning intended to emphasize how subjects feel in social settings during conducted research.

Scholars have marveled in amazement at the power public opinion has in making regulations, norms, and moral rules triumph over the individual self without ever troubling legislators, governments, or courts for assistance.

Opinion

"Common Opinion" is how the Scottish social philosopher David Hume referred to public opinion in his 1739 published work A Treatise of Human Nature. Agreement and a sense of the common are what lay behind the English and French "opinion." In researching the term opinion (Meinung in German) researchers were led back to Plato's Republic. In Plato's Republic, a quote from Socrates concluded that opinion takes the middle position. Immanuel Kant considered the opinion to be an "insufficient judgment, subjectively as well as objectively." How valuable opinion may be was left out; however, the fact that it is suggested to be unified agreement of a population or segment of the population, was still considered.

Public opinion

The term public opinion first emerged in France during the eighteenth century. The definition of public opinion has been debated over time. There has not been much progress in locking in one classification of the phrase public opinion, however Hermann Oncken, a German historian, stated

Whoever desires to grasp and define the concept of public opinion will recognize quickly that he is dealing with a Proteus, a being that appears simultaneously in a thousand guises, both visible and as a phantom, impotent and surprisingly efficacious, which presents itself in innumerable transformations and is forever slipping through our fingers just as we believe we have a firm grip on it... That which floats and flows cannot be understood by being locked up in a formula... After all, when asked, everyone knows exactly what public opinion means.

It was said to be a "fiction that belonged in a museum of the history of ideas; it could only be of historical interest."

In contradiction to that quote, the term public opinion never fell out of use. During the early 1970s, Elisabeth Noelle-Neumann was creating the theory of the spiral of silence. She was attempting to explain why Germans who disagreed with Hitler and the Nazis remained silent until after his regime ended. Behavior like that has come to be known as the spiral of silence theory. Noelle-Neumann began to question if she was indeed getting a handle on what public opinion actually was. "The spiral of silence might be one of the forms in which public opinion appeared; it might be a process through which a new, youthful public opinion develops or whereby the transformed meaning of an old opinion spreads."

The American sociologist Edward Ross described public opinion in 1898 using the word "cheap". "The equation of 'public opinion' with 'ruling opinion' runs like a common thread through its many definitions. This speaks to the fact that something clinging to public opinion sets up conditions that move individuals to act, even against their own will."

Other scholars point out that the emergence of the public opinion depends on an open public discourse rather than "on the discipline imposed by an apparent majority dominant enough to intimidate but whose views may or may not support actions that are in the common interest." They have also considered whose opinion establishes public opinion, assumed to be persons of a community who are ready to express themselves responsibly about questions of public relevance. Scholars have also looked into the forms of public opinion, said to be those that are openly expressed and accessible; opinions that are made public, especially in the mass media. Controversy surrounding this term spiraled around both words combining to form the phrase.

Neumann (1955) suggests two concepts on public opinion:

Public Opinion as Rationality: The public opinion or "dominant view" comes after conscious rational public discussion. Childs (1965) and Wilson (1933) believe that "the rational model is based on the notion of an enlightened, rational public that is willing to and capable of participating in political processes." In all, it is political and necessary for generating social change.

Public Opinion as Social Control: This is at the root of the spiral of silence theory. It means that "opinions that can be expressed without risking sanctions or social isolation, or opinions that have to be expressed in order to avoid isolation (Noelle-Neumann 1983). Social systems require cohesion. To achieve this, individuals are threatened with social isolation.

In mass media contexts

Media and public opinion

Mass media's effects on both public opinion and the perception of the public opinion are central to the spiral of silence theory. One of the earliest works that called attention to the relationship between media and the formation of public opinion was Walter Lippmann's book "Public Opinion", published in 1922. Ideas of Lippmann regarding the effects of media influenced the emergence of the spiral of silence theory. As she is building the spiral theory, Noelle-Neumann states "the reader can only complete and explain the world by making use of a consciousness which in large measure has been created by the mass media."

Agenda-setting theory is another work that Noelle-Neumann builds on as she is characterizing media's effect on the public opinion. Agenda-setting theory describes the relationship between media and public opinion by asserting that the public importance of an issue depends on its salience in the media. Along with setting the agenda, the media further determine the salient issues through a constant battle with other events attempting to gain place in the agenda. The media battle with these news alternatives by creating "pseudo-crises" and "pseudo-novelties."

Media's characteristics as a communication tool further affect people's perception of their own ideas in regard to the public opinion. According to Noelle-Neumann, the media are a "one-sided, indirect, public form of communication, contrasting threefold with the most natural form of human communication, the conversation." When an issue hits the media and proves salient, a dominant point of view usually emerges. These characteristics of the media in particular further overwhelm one's individual ideas.

While some media communication theories assume a passive audience, such as the Hypodermic Needle model, the spiral model assumes an active audience "who consumes media products in the context of their personal and social goals." Knowledge "gained from the mass media may offer ammunition for people to express their opinions and offer a rationale for their own stance." Ho et al. point out that "among individuals who paid high amount of media attention, those who have a low fear of isolation were significantly more likely to offer a rationale for their own opinion than were those who have a high fear of isolation."

Noelle-Neuman regards media as central to the formulation of the Spiral of Silence Theory, whereas some scholars argue whether the dominant idea in one's social environment overwhelms the dominant idea that media propose as the perceived social norm. Some empirical research align with this perspective; suggesting that the "micro-climate" of an individual overwhelms the effects of the media. Other articles further suggest that talking with others is the primary way of understanding the opinion climate.

Social media

Current literature suggests that the spiral model can be applied to the social media context. Researchers, Chaudhry & Gruzd (2019) found that social media actually weakens this theory. They contest that the spiral of silence suggests that the minority are uncomfortable expressing their opinions because of the fear of isolation, but, "the vocal minority are comfortable expressing unpopular views, questioning the explanatory power of this popular theory in the online context."

However, in another study, Gearhart and Zhang examine whether or not the use of social media will increase people's motivation to express their opinions about political issues. The results suggest that social media users "who have received a strong negative reaction to their politically related posts are likely to censor themselves, exemplifying the spiral of silence effect". Another study found that the fear of isolation causes people to not want to share their opinion on social media in the first place. Similar to the Gearhart and Zhang study, results from this study showed that people are more likely to self-censor information on social media by not posting some things that are political, choosing what and what not to follow or like, etc.

Another research confirms the positive relationship between speaking out and issue importance on the social media context as well: individuals who view gay bullying as a significant social issue are more likely to comment on Facebook.

Artificially generated social engagement is also worth noting. As social media becomes more and more important in our daily lives, deceptive social bots have been successfully applied for manipulating online conversations and opinions. Social bots are social media accounts managed by computer algorithms. They can automatically generate content and interact with human users, often impersonating or imitating humans. Current research shows that "social bots" are being used on a large scale to control the opinion climate to influence public opinion on social media. In some cases only a small number of social bots can easily direct public opinion on social media and trigger a spiral of silence model. For example, scholars find out that social bots can affect political discussion around the 2016 U.S. presidential election and the 2017 French presidential election.

Assumptions

Perception

The Spiral of Silence Theory rests on the assumption that individuals will scan their environment to assess the climate to possibly find the dominant point of view. Perception matters because these opinions influence an individual's behavior and attitudes. Sherif (1967) believes individuals use frames of reference based on past experience to inform their perception -- "social environment as a frame of reference for interpreting new information has important implications for public opinion research." It is also worth mentioning that the assessment of one's social environment may not always correlate with reality.

Quasi-statistical organ

Noelle-Neumann attributed this ability of assessing opinion climate on an issue to the so-called "quasi-statistical organ", which refers to how individuals unconsciously assess the distribution of viewpoints and the chances that certain viewpoints will succeed over others. People assume they can sense and figure out what others are thinking.

The Mass media play a large part in determining what the dominant opinion is, since our direct observation is limited to a small percentage of the population. The mass media have an enormous impact on how public opinion is portrayed, and can dramatically impact an individual's perception about where public opinion lies, whether or not that portrayal is factual.

Pluralistic ignorance

Pluralistic ignorance may occur in some cases in which the minority opinion is incorrectly accepted as the norm.[1] Group members may be privately rejecting a norm, but may falsely assume that other group members accept it. This phenomenon, also known as a collective illusions, is when people in a group think everyone else has a different opinion from theirs and go along with the norm.

Fear of isolation

The spiral of silence can lead to a social group or society isolating or excluding members due to the members' opinions. This stipulates that individuals have a fear of isolation. This fear of isolation consequently leads to remaining silent instead of voicing opinions.

The fear of isolation is the "engine that drives the spiral of silence". Essentially, people fear becoming social isolates and thus take measures to avoid such a consequence, as demonstrated by psychologist Solomon Asch in the Asch conformity experiments. People feel more comfortable agreeing with the dominant opinions instead of expressing their own ideas.

An underlying idea of the spiral of silence theory is that public opinion acts as a form of social control. According to Noelle-Neumann's definition this key concept describes "opinions on controversial issues that one can express in public without isolating oneself". This assumption supposed that public opinion is governed by norms and conventions, the violation of which will lead to sanctions against those individuals. Going off of this assumption that going against public opinion will lead to social sanctions, Noelle-Neumann assumes that human beings have an inherent fear of isolation and will adapt their behavior so that they will not be isolated from others. This “fear of isolation” is so strong that people will not express opinions if they assume that these opinions differ from public opinion.

How does the fear of isolation function?

This fear of social isolation is a central concept in Noelle-Neumann's theory but throughout different studies on the theory it has been conceptualized in many different ways. Some researchers have considered fear of social isolation to be transitory and triggered by the exposure to a situation in which an individual is expected to express an opinion. In this conceptualization an individual's perception of the opinion climate in a specific situation would trigger the fear of isolation in that moment.

Other researchers have argued that instead of a situation-specific reaction, fear of social isolation can be viewed as individual characteristic that varies between people and leads individuals to continuously monitor their environment for cues about the opinion climate. While there are individuals who generally do not suffer from a fear of isolation (what Noelle-Neumann referred to as Hardcores) others are constantly aware of their social environment and faced with a constant fear of isolation. Individuals who bear this characteristic of fear of social isolation and at the same time perceive their opinion to be incongruent with the majority opinion climate are less likely to be willing to voice their opinion. In this line of spiral of silence research fear of social isolation is a key concept in formation of public opinion, however research has often assumed this conceptualization as a fact without empirical proof or been inconsistent in the empirical measurement of this phenomenon.

Recent research has been able to capture the concept of fear of social isolation in a more reliable and consistent way. One example is research conducted by Mathes (2012) in which the researchers used an individual differences approach based on individual's character traits and measured individual's fear of social isolation using psychometric properties. Mathes (2012), as well as other researchers, considers fear of social isolation to be a subsequent reaction to encountering a perceived hostile opinion climate which in turn leads the individual to not voice their own opinions and therefore sets in motion the spiral of silence.

Although many accept fear of isolation to be the motivation behind the theory, arguments have been made for other causal factors. For example, Lasorsa proposed it may be less a fear of isolation fueling the spiral, and more about political interest (in the case of political debate) and self-efficacy. From a more positive standpoint, Taylor suggested the benefits of opinion expression, whether that opinion was common or not, to be the motivation. When studying the willingness to discuss an issue so divisive as abortion, Salmon and Neuwirth found only "mixed supportive evidence" for fear of isolation, and instead found that knowledge and personal concern of the issue played important roles. More examples follow at the end of the article.

Responses to disputed and undisputed opinions

Where opinions are relatively definite and static – customs, for example – one has to express or act according to this opinion in public or run the risk of becoming isolated. In contrast, where opinions are in flux, or disputed, the individual will try to find out which opinion he can express without becoming isolated.

Vocal minority and hardcore

The theory explains a vocal minority (the complement of the silent majority) by stating that people who are highly educated, or who have greater affluence, and the few other cavalier individuals who do not fear isolation (if that is accepted to be the causal factor), are likely to speak out regardless of public opinion. It further states that this minority is a necessary factor of change while the compliant majority is a necessary factor of stability, with both being a product of evolution. There is a vocal minority, which remains at the top of the spiral in defiance of threats of isolation.

This theory calls these vocal minorities the hardcore nonconformist or the avant-garde. Hardcore nonconformists are "people who have already been rejected for their beliefs and have nothing to lose by speaking out." The hardcore has the ability to reconfigure majority opinion, while the avant-garde are "the intellectuals, artists, and reformers in the isolated minority who speak out because they are convinced they are ahead of the times."

Hardcore is best understood when the majority voices loses power in public opinion due to a lack of alternatives. People's opinions may affect narrow-minded views as a result of the hard core's efforts to educate the public. Hardcore may be instrumental in changing public opinion even though it is frequently engaged in irrational acts to prove their point.

Real world application of the theory

The spiral of silence has brought insight regarding diverse topics, ranging from speaking about popular culture phenomena to smoking. Considering that the spiral of silence is more likely to occur in controversial issues and issues with a moral component, many scholars have applied the theory to controversial topics, such as abortionaffirmative actioncapital punishment, mandatory COVID-19 vaccines and masking.

Social capital

The spiral of silence theory can be also applied to social capital context. Recent studies see social capital as "a variable that enables citizens to develop norms of trust and reciprocity, which are necessary for successful engagement in collective activities". One study examines three individual-level indicators of social capital: civic engagement, trust and neighborliness, and the relationship between these indicators and people's willingness to express their opinions and their perception of support for one's opinions. The results suggest that civic engagement has a direct effect on people's willingness to express their opinions and neighborliness and trust had direct positive effects on people's perception of support for one's opinions. Also, the study shows that "only a direct (but not indirect) effect of civic engagement on opinion expression further highlights a potential difference between bonding and bridging social capital".

Cross-cultural studies

Existing literature prior to the spiral of silence theory suggest a relationship between social conformity and culture, motivating communication scholars to conduct cross-cultural analysis of the theory. Scholars in the field of psychology in particular previously addressed the cultural variance involved in the conformity to the majority opinion. More recent studies confirm the link between conformity and culture: a meta-analysis regarding Asch conformity experiments, for example, suggest that collectivist cultures are more likely to exhibit conformity than the individualistic cultures.

The United States and Taiwan

"A Cross-Cultural Test of the Spiral of Silence" by Huiping Huang analyzes the results of a telephone survey done in Taiwan and the United States. The hypotheses tested were the beliefs that the United States is an "individualistic" society, while Taiwan is a "collectivist" society. This suggested that the spiral of silence is less likely to be activated in the United States, because individuals are more likely to put emphasis on their personal goals. They put the "I" identity over the "we" identity, and strive for personal success. Therefore, it was hypothesized that they would be more likely to speak out, regardless of if they are in the minority. On the other hand, it was predicted that individuals in Taiwan put more emphasis on the collective goal, so they would conform to the majority influence in hopes of avoiding tension and conflict. The study also tested the effect of motives, including self-efficacy and self-assurance.

Telephone surveys were conducted; the citizens of the United States were questioned in regard to American involvement in Somalia, and the citizens of Taiwan about the possibility of a direct presidential election. Both issues focused on politics and human rights, and were therefore comparable. Respondents were asked to choose "favor", "neutral" or "oppose" in regard to the categories of themselves, family and friends, the media, society, and society in the future about the given issue. Measurements were also taken regarding the individualism and collectivism constructs, and the "motives of not expressing opinion" based on a 1–10 and 1–5 scale respectively, in approval of given statements.

Results showed support for the original hypothesis. Overall, Americans were more likely to speak out than Taiwanese. Being incongruous with the majority lessened the motivation of the Taiwanese to speak out (and they had a higher collectivist score), but had little effect on the Americans. In Taiwan, future support and belief of society played a large role in likeliness to voice an opinion, and support that the activation of the spiral of silence is in effect. In the United States, it was hypothesized that because they were more individualistic, they would be more likely to speak out if in the minority, or incongruous group. However, this was not true, but Huang suggests that perhaps the issue chosen was not directly prevalent, and therefore, they found it "unnecessary to voice their objections to the majority opinion." Lack of self-efficacy led to lack of speaking out in both countries.

Basque nationalism

Basque Nationalism and the Spiral of Silence is an article by Spencer and Croucher that analyzes the public perception of ETA (Euskadi Ta Askatasuna, a militant separatist group) in Spain and France. This study was conducted in a similar way as above, with Basque individuals from Spain and France being questioned about their support of ETA. They were asked questions such as "How likely would you be to enter into a conversation with a stranger on a train about ETA?" Taken into consideration were the cultural differences of the two different regions in which ETA existed.

The results supported the theory of the spiral of silence. While there was a highly unfavorable opinion of the group, there was a lack of an outcry to stop it. Individuals claimed that they were more likely to voice their opinions to non-Basques, suggesting that they have a "fear of isolation" in regard to fellow Basques. Furthermore, the Spanish individuals questioned were more likely to be silent because of their greater proximity to the violent acts.

Perceptions in the classroom

One study by Henson and Denker "investigates perceptions of silencing behaviors, political affiliation, and political differences as correlates to perceptions of the university classroom climates and communication behaviors." They looked at whether students' view of the classroom changes whether they perceive the instructor and other classmates with a different political affiliation, with the instructor and other classmates communicating using silencing behaviors. The article stated that little has been investigated into student-teacher interactions in the classroom, and how the students are influenced. The goal of the article was to "determine how political ideas are expressed in the university classrooms, and thus, assess the influence of classroom communication on the perceptions of political tolerance."

The article claimed that university classrooms are an adequate place to scrutinize the spiral of silence theory because it is a place that has interpersonal, cultural, media, and political communication. Henson and Denker said, "Because classroom interactions and societal discourse are mutually influential, instructors and students bring their own biases and cultural perspectives into the classroom."

The study researched whether there was a correlation between students' perception that they were being politically silenced and their perceived differences in student-instructor political affiliation. The study also questioned whether there was any connection between the perceived climate and the similarity of the student and instructor on their political affiliations. The researchers used participants from a Midwestern university's communication courses. The students answered a survey over their perceptions of political silencing, classroom climate, and the climate created by the instructor. The results of this research found that there is a positive relationship of the perceived similarities in a political party and ideological differences of the student and instructor to perceived greater political silencing.

In computer-mediated communication

While the studies regarding the spiral of silence theory focused on face-to-face interaction before 2000, the theory was later applied to a computer-mediated communication environment. The first study in this context analyzed communication behaviors in online chat rooms regarding the issue of abortion, and revealed that minority opinion holders were more likely to speak out, whereas their comments remained neutral. Another study focused on the Korean bulletin board postings regarding the national election, and found a relationship between online postings and the presentation of candidates in the mainstream media. The third study focuses on the online review system, suggesting that the fear of isolation tend to reduce the willingness of members to voice neutral and negative reviews. The spiral of silence theory is extended "into the context of non-anonymous multichannel communication platforms" and "the need to consider the role of communicative affordances in online opinion expression" is also addressed.

The rising influence of the internet and social media

Isolating the factors that remove isolation

The concept of isolation has a variety of definitions, dependent upon the circumstances it is investigated in. In one instance the problem of isolation has been defined as social withdrawal, defined as low relative frequencies of peer interaction. Other researchers have defined isolation as low levels of peer acceptance or high levels of peer rejection. Research that considers isolation with regard to the Internet either focuses on how the Internet makes individuals more isolated from society by cutting off their contact from live human beings or how the Internet decreases social isolation of people by allowing them to expand their social networks and giving them more means to stay in touch with friends and family. Since the development of the Internet, and in particular the World Wide Web, a wide variety of groups have come into existence, including Web and Internet Relay Chat (IRC), newsgroups, multiuser dimensions (MUDs), and, more recently, commercial virtual communities. The theories and hypotheses about how Internet-based groups impact individuals are numerous and wide-ranging. Some researchers view these fast growing virtual chat cliques, online games, or computer-based marketplaces as a new opportunity, particularly for stigmatized people, to take a more active part in social life.

Traditionally, social isolation has been presented as a one-dimensional construct organized around the notion of a person's position outside the peer group and refers to isolation from the group as a result of being excluded from the group by peers. From children to adults, literature shows that people understand the concept of isolation and fear the repercussions of being isolated from groups of which they are a member. Fearing isolation, people did not feel free to speak up if they feel they hold dissenting views, which means people restrict themselves to having conversation with like-minded individuals, or have no conversation whatsoever. Witschge further explained, "Whether it is fear of harming others, or fear to get harmed oneself, there are factors that inhibit people from speaking freely, and which thus results in a non-ideal type of discussion, as it hinders diversity and equality of participants and viewpoints to arise fully."

The medium of the Internet has the power to free people from the fear of social isolation, and in doing so, shuts down the spiral of silence. One article demonstrates that social media can weaken the fear of isolation. The research shows that the vocal minority who hold racist viewpoints are willing to express unpopular views on Facebook. The Internet allows people to find a place where they can find groups of people with like mindsets and similar points of view. Van Alstyne and Brynjolfsson stated that "Internet users can seek out interactions with like-minded individuals who have similar values, and thus become less likely to trust important decisions to people whose values differ from their own." The features of the Internet could not only bring about more people to deliberate by freeing people of psychological barriers, but also bring new possibilities in that it "makes manageable large-scale, many-to-many discussion and deliberation." Unlike traditional media that limit participation, the Internet brings the characteristics of empowerment, enormous scales of available information, specific audiences can be targeted effectively and people can be brought together through the medium.

Online versus offline

The Internet is a place where many reference and social groups are available with similar views. It has become a place where it appears that people have less of a fear of isolation. One research article examined individuals' willingness to speak their opinion online and offline. Through survey results from 305 participants, a comparison and contrast of online and offline spiral of silence behaviors was determined. Liu and Fahmy stated that "it is easy to quit from an online discussion without the pressure of complying with the majority group." This is not to say that a spiral of silence does not occur in an online environment. People are still less likely to speak out, even in an online setting, when there is a dominant opinion that differs from their own. But people in the online environment will speak up if someone has a reference group that speaks up for them.

Online, the presence of one person who encourages a minority point of view can put an end to a spiral of silence. Studies of the spiral of silence in online behavior have not acknowledged that a person may be more likely to speak out against dominant views offline as well. The person might have characteristics that make them comfortable speaking out against dominant views offline, which make them just as comfortable speaking out in an online setting.

Although research suggests that people will disclose their opinions more often in an online setting, silencing of views can still occur. One study indicates that people on Facebook are less willing to discuss the Snowden and NSA stories than an offline situation such as a family dinner or public meeting.[86] Another research article examined the influence of different opinion climates in online forums (opinion congruence with the majority of forum participants vs. website source) and found personal opinion congruence was more influential than the online site in which the forum is situated in.[87] Nekmat and Gonzenbach said it might be worth researching whether the factors in these studies or other factors cause people to be more comfortable when it comes to speaking their mind while online.[87]

Heterogeneity and anonymity

The nature of the Internet facilitates not only the participation of more people, but also a more heterogeneous group of people. Page stated, "The onward rush of electronic communications technology will presumably increase the diversity of available ideas and the speed and ease with which they fly about and compete with each other." The reason people engage in deliberations is because of their differences, and the Internet allows differences to be easily found. The Internet seems the perfect place to find different views of a very diverse group of people who are at the same time open to such difference and disagreement needed for deliberation. Noelle-Neumann's initial idea of cowering and muted citizens is difficult to reconcile with empirical studies documenting uninhibited discussion in computer-mediated contexts such as chat rooms and newsgroups.

The Internet provides an anonymous setting, and it can be argued that in an anonymous setting, fears of isolation and humiliation would be reduced. Wallace recognized that when people believe their actions cannot be attributed to them personally, they tend to become less inhibited by social conventions and restraints. This can be very positive, particularly when people are offered the opportunity to discuss difficult personal issues under conditions in which they feel safer.

The groups' ability to taunt an individual is lessened on the Internet, thus reducing the tendency to conform. Wallace goes on to summarize a number of empirical studies that do find that dissenters feel more liberated to express their views online than offline, which might result from the fact that the person in the minority would not have to endure taunts or ridicule from people that are making up the majority, or be made to feel uncomfortable for having a different opinion. Stromer-Galley considered that "an absence of non-verbal cues, which leads to a lowered sense of social presence, and a heightened sense of anonymity" frees people from the psychological barriers that keep them from engaging in a face-to-face deliberation.

The crux of the spiral of silence is that people believe consciously or subconsciously that the expression of unpopular opinions will lead to negative repercussions. These beliefs may not exist on the Internet for several reasons. First, embarrassment and humiliation depends on the physical presence of others. In computer-mediated communication, physical isolation often already exists and poses no further threat. Second, a great deal of normative influence is communicated through nonverbal cues, such as eye contact and gestures, but computer-mediated communication typically precludes many of these cues. Third, Kiesler, Siegel, and McQuire observe that nonverbal social context cues convey formality and status inequality in face-to-face communication. When these cues are removed, the importance of social status as a source of influence recedes. Group hierarchies that develop in face-to-face interaction emerge less clearly in a mediated environment. The form and consequences of conformity influence should undergo significant changes given the interposition of a medium that reduces the social presence of participants. Social presence is defined as the degree of salience of the other person in the interaction or the degree to which the medium conveys some of the person's presence.

Equality

An important issue in obtaining heterogeneity in conversation is equal access for all the participants and equal opportunities to influence in the discussion. When people believe they are ignorant about a topic, incapable to participate in a discussion or not equal to their peers, they tend to not even become involved in a deliberation. When people do decide to participate, their participation might be overruled by dominant others, or their contribution might be valued less or more, depending on their status. Dahlberg praises the Internet for its possibility to liberate people from the social hierarchies and power relations that exist offline: "The 'blindness' of cyberspace to bodily identity... [is supposed to allow] people to interact as if they were equals. Arguments are said to be assessed by the value of the claims themselves and not the social position of the poster".

Gastil sees this feature as one of the strongest points of the Internet: "if computer-mediated interaction can consistently reduce the independent influence of status, it will have a powerful advantage over face-to-face deliberation". While status cues are difficult to detect, perceptions about the status converge, and this lessens stereotyping and prejudice.

It may be that people do feel more equal in online forums than they feel offline. Racism, ageism, and other kinds of discrimination against out groups "seems to be diminishing because the cues to out-group status are not as obvious". Next to this, the Internet has rapidly and dramatically increased the capacities to develop, share and organize information, realizing more equality of access to information.

Methodological research approaches

The relationship between the perception of public opinion and willingness to speak-up is mainly measured through surveys. Surveys respondents are often asked whether they would reveal their opinions given a hypothetical situation, right after their opinions about the public opinion and their opinion is received. Whether asking hypothetical questions can reflect real life cases was questioned by some communication scholars, leading to a criticism of this methodology as not being able to capture what the respondent would do in a real-life situation. A research study addressed this criticism by comparatively testing a spiral model both in a hypothetical survey and in a focus group. The findings are in line with the critic of hypothetical survey questions, demonstrating a significant increase in the spiral of silence in focus groups.

Among different approaches to survey methodology, cross-sectional study design is the leading method employed to analyze and test the theory. Cross-sectional design involves the analysis of the relationship between public opinion and willingness to speak at one point in time.

While many of the researchers employ cross-sectional design, some scholars employed panel data. Under this methodology, three specific approaches have been used. Noelle-Neumann herself tested the theory from the aggregate level. Using this approach, the change process is "observed by comparing the absolute share of people perceiving a majority climate with people willing to express their views over time." The second approach that has been used in spiral of silence research is conducting separate regressions for each panel survey wave. The drawback for this approach is that the individual change of climate and opinions perception is ignored. The last approach a few scholars used in conducting spiral of silence researches is to use changed scores as dependent variables. However, as intuitive as this approach may be, it "leads to well-documented difficulties with respect to statistical properties, such as regression to the mean or the negative correlation of the change score with the time one state".

Criticisms

The critics of this theory most often claim that individuals have different influences that affect whether they speak out or not.

Research indicates that people fear isolation in their small social circles more than they do in the population at large. Within a large nation, one can always find a group of people who share one's opinions, however people fear isolation from their close family and friends more in theory. Research has demonstrated that this fear of isolation is stronger than the fear of being isolated from the entire public, as it is typically measured.

Scholars have argued that both personal characteristics and various cultures among different groups will have influences on whether a person will willingly speak out. If one person "has a positive self-concept and lacks a sense of shame, that person will speak out regardless of how she or he perceives the climate of public opinion." Another influence critics give for people choosing not to speak out against public opinion is culture. Some cultures are more individualistic, which would support more of an individual's own opinion, while collectivist cultures support the overall group's opinion and needs. Gender can be also considered as a cultural factor. In some cultures, women's "perception of language, not public opinion, forces them to remain quiet." Scheufele & Moy, further assert that certain conflict styles and cultural indicators should be used to understand these differences.

The nature of issues will influence the dynamic processes of the spiral of silence. Yeric and Todd present three issues type, including enduring issues that will be discussed by the public for a long time; emerging issues that are new to the public but have the potential to become enduring issues; and the transitory issues, which don't stay in the public consciousness for very long but come up from time to time. The research suggests that issues difference affects people's willingness to express. Facebook users are more likely to post their real thoughts on emerging issues such as gay marriage in an incongruent opinion climate.

Another criticism of the spiral of silence research is that the research designs do not observe the movement in the spiral over time. Critics propose that Noelle-Neumann's emphasis on time in the formation of the spiral should reflect on the methodology as well, and the dynamic nature of the spiral model should be acknowledged. They argue that the spiral of silence theory involves a "time factor", considering that the changes in public opinion eventually lead to change in people's assessments of the public opinion. Also, according to Spilchal, the spiral of silence theory "ignores the evidence of the historical development of public opinion, both in theory and practice, through the extension of suffrage, organisation of political propaganda groups, the establishment of pressure groups and political parties, the eligibility of ever wider circles of public officials and, eventually, the installation of several forms of direct democracy."

Some scholars also provide understandings of the theory in the contemporary society by pointing out that "it is not so much the actual statistical majority that generates pressure for conformity as it is the climate of opinion conveyed in large measure by the media." Under the great influence by the media coverage, the climate of opinion "is not invariably an accurate reflection of the distribution of opinions within the polity."

Further, Scheufele & Moy find problems in the operationalization of key terms, including willingness to speak out. This construct should be measured in terms of actually speaking out, not voting or other conceptually similar constructs. Conformity experiments have no moral component, yet morality is a key construct in the model. These conformity experiments, particularly those by Asch, form part of the base of the theory. Scholars question whether these conformity experiments are relevant to the development of the spiral of silence.

False dilemmas and silence of consistency

While the existence of groups with opinions other than those that are supposed to be dominant in a society provide a space for some people to express seemingly unpopular opinions, assumptions in such groups that criticism of their underrepresented opinion equates to support for society's mainstream views is a source of false dilemmas.

Some research indicates that such false dilemmas, especially when there are inconsistencies both in mainstream views and in organized opposition views, causes a spiral of silence that specifically silences logically consistent third, fourth or higher number viewpoint criticism.

Epistemology

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Epistemology

Epistemology is the branch of philosophy that examines the nature, origin, and limits of knowledge. Also called "the theory of knowledge", it explores different types of knowledge, such as propositional knowledge about facts, practical knowledge in the form of skills, and knowledge by acquaintance as a familiarity through experience. Epistemologists study the concepts of belief, truth, and justification to understand the nature of knowledge. To discover how knowledge arises, they investigate sources of justification, such as perception, introspection, memory, reason, and testimony.

The school of skepticism questions the human ability to attain knowledge while fallibilism says that knowledge is never certain. Empiricists hold that all knowledge comes from sense experience, whereas rationalists believe that some knowledge does not depend on it. Coherentists argue that a belief is justified if it coheres with other beliefs. Foundationalists, by contrast, maintain that the justification of basic beliefs does not depend on other beliefs. Internalism and externalism debate whether justification is determined solely by mental states or also by external circumstances.

Separate branches of epistemology focus on knowledge in specific fields, like scientific, mathematical, moral, and religious knowledge. Naturalized epistemology relies on empirical methods and discoveries, whereas formal epistemology uses formal tools from logic. Social epistemology investigates the communal aspect of knowledge, and historical epistemology examines its historical conditions. Epistemology is closely related to psychology, which describes the beliefs people hold, while epistemology studies the norms governing the evaluation of beliefs. It also intersects with fields such as decision theory, education, and anthropology.

Early reflections on the nature, sources, and scope of knowledge are found in ancient Greek, Indian, and Chinese philosophy. The relation between reason and faith was a central topic in the medieval period. The modern era was characterized by the contrasting perspectives of empiricism and rationalism. Epistemologists in the 20th century examined the components, structure, and value of knowledge while integrating insights from the natural sciences and linguistics.

Definition

Epistemology is the philosophical study of knowledge and related concepts, such as justification. Also called theory of knowledge, it examines the nature and types of knowledge. It further investigates the sources of knowledge, like perception, inference, and testimony, to understand how knowledge is created. Another set of questions concerns the extent and limits of knowledge, addressing what people can and cannot know. Central concepts in epistemology include belief, truth, evidence, and reason. As one of the main branches of philosophy, epistemology stands alongside fields like ethics, logic, and metaphysics. The term can also refer specific positions of philosophers within this branch, as in Plato's epistemology and Immanuel Kant's epistemology.

Epistemology explores how people should acquire beliefs. It determines which beliefs or forms of belief acquisition meet the standards or epistemic goals of knowledge and which ones fail, thereby providing an evaluation of beliefs. The fields of psychology and cognitive sociology are also interested in beliefs and related cognitive processes, but examine them from a different perspective. Unlike epistemology, they study the beliefs people actually have and how people acquire them instead of examining the evaluative norms of these processes. In this regard, epistemology is a normative discipline, whereas psychology and cognitive sociology are descriptive disciplines. Epistemology is relevant to many descriptive and normative disciplines, such as the other branches of philosophy and the sciences, by exploring the principles of how they may arrive at knowledge.

The word epistemology comes from the ancient Greek terms ἐπιστήμη (episteme, meaning knowledge or understanding) and λόγος (logos, meaning study of or reason), literally, the study of knowledge. Despite its ancient roots, the word itself was only coined in the 19th century to designate this field as a distinct branch of philosophy.

Central concepts

Epistemologists examine several foundational concepts to understand their essences and rely on them to formulate theories. Various epistemological disagreements have their roots in disputes about the nature and function of these concepts, like the controversies surrounding the definition of knowledge and the role of justification in it.

Knowledge

Knowledge is an awareness, familiarity, understanding, or skill. Its various forms all involve a cognitive success through which a person establishes epistemic contact with reality. Epistemologists typically understand knowledge as an aspect of individuals, generally as a cognitive mental state that helps them understand, interpret, and interact with the world. While this core sense is of particular interest to epistemologists, the term also has other meanings. For example, the epistemology of groups examines knowledge as a characteristic of a group of people who share ideas. The term can also refer to information stored in documents and computers.

Knowledge contrasts with ignorance, often simply defined as the absence of knowledge. Knowledge is usually accompanied by ignorance because people rarely have complete knowledge of a field, forcing them to rely on incomplete or uncertain information when making decisions. Even though many forms of ignorance can be mitigated through education and research, certain limits to human understanding result in inevitable ignorance. Some limitations are inherent in the human cognitive faculties themselves, such as the inability to know facts too complex for the human mind to conceive. Others depend on external circumstances when no access to the relevant information exists.

Epistemologists disagree on how much people know, for example, whether fallible beliefs can amount to knowledge or whether absolute certainty is required. The most stringent position is taken by radical skeptics, who argue that there is no knowledge at all.

Types

Black and white photo of a man wearing a dark suit, a white shirt, and a tie
Bertrand Russell originated the distinction between propositional knowledge and knowledge by acquaintance.

Epistemologists distinguish between different types of knowledge. Their primary interest is in knowledge of facts, called propositional knowledge. It is theoretical knowledge that can be expressed in declarative sentences using a that-clause, like "Ravi knows that kangaroos hop". For this reason, it is also called knowledge-that. Epistemologists often understand it as a relation between a knower and a known proposition, in the case above between the person Ravi and the proposition "kangaroos hop". It is use-independent since it is not tied to one specific purpose, unlike practical knowledge. It is a mental representation that embodies concepts and ideas to reflect reality. Because of its theoretical nature, it is typically held that only creatures with highly developed minds, such as humans, possess propositional knowledge.

Propositional knowledge contrasts with non-propositional knowledge in the form of knowledge-how and knowledge by acquaintance. Knowledge-how is a practical ability or skill, like knowing how to read or how to prepare lasagna. It is usually tied to a specific goal and not mastered in the abstract without concrete practice. To know something by acquaintance means to have an immediate familiarity with or awareness of it, usually as a result of direct experiential contact. Examples are "familiarity with the city of Perth", "knowing the taste of tsampa", and "knowing Marta Vieira da Silva personally".

Painting of a man with gray hair in a formal dark attire
The analytic–synthetic distinction has its roots in the philosophy of Immanuel Kant.

Another influential distinction in epistemology is between a posteriori and a priori knowledge. A posteriori knowledge is knowledge of empirical facts based on sensory experience, like "seeing that the sun is shining" and "smelling that a piece of meat has gone bad". This type of knowledge is associated with the empirical science and everyday affairs. A priori knowledge, by contrast, pertains to non-empirical facts and does not depend on evidence from sensory experience, like knowing that . It belongs to fields such as mathematics and logic. The distinction between a posteriori and a priori knowledge is central to the debate between empiricists and rationalists regarding whether all knowledge depends on sensory experience.

A closely related contrast is between analytic and synthetic truths. A sentence is analytically true if its truth depends only on the meanings of the words it uses. For instance, the sentence "all bachelors are unmarried" is analytically true because the word "bachelor" already includes the meaning "unmarried". A sentence is synthetically true if its truth depends on additional facts. For example, the sentence "snow is white" is synthetically true because its truth depends on the color of snow in addition to the meanings of the words snow and white. A priori knowledge is primarily associated with analytic sentences, whereas a posteriori knowledge is primarily associated with synthetic sentences. However, it is controversial whether this is true for all cases. Some philosophers, such as Willard Van Orman Quine, reject the distinction, saying that there are no analytic truths.

Analysis

The analysis of knowledge is the attempt to identify the essential components or conditions of all and only propositional knowledge states. According to the so-called traditional analysis, knowledge has three components: it is a belief that is justified and true. In the second half of the 20th century, this view was challenged by a series of thought experiments aiming to show that some justified true beliefs do not amount to knowledge. In one of them, a person is unaware of all the fake barns in their area. By coincidence, they stop in front of the only real barn and form a justified true belief that it is a real barn. Many epistemologists agree that this is not knowledge because the justification is not directly relevant to the truth. More specifically, this and similar counterexamples involve some form of epistemic luck, that is, a cognitive success that results from fortuitous circumstances rather than competence.

Venn diagram with circles for true beliefs, justified beliefs, and knowledge
The so-called traditional analysis says that knowledge is justified true belief. Edmund Gettier tried to show that some justified true beliefs do not amount to knowledge.

Following these thought experiments, philosophers proposed various alternative definitions of knowledge by modifying or expanding the traditional analysis. According to one view, the known fact has to cause the belief in the right way. Another theory states that the belief is the product of a reliable belief formation process. Further approaches require that the person would not have the belief if it was false, that the belief is not inferred from a falsehood, that the justification cannot be undermined, or that the belief is infallible. There is no consensus on which of the proposed modifications and reconceptualizations is correct. Some philosophers, such as Timothy Williamson, reject the basic assumption underlying the analysis of knowledge by arguing that propositional knowledge is a unique state that cannot be dissected into simpler components.

Value

The value of knowledge is the worth it holds by expanding understanding and guiding action. Knowledge can have instrumental value by helping a person achieve their goals. For example, knowledge of a disease helps a doctor cure their patient. The usefulness of a known fact depends on the circumstances. Knowledge of some facts may have little to no uses, like memorizing random phone numbers from an outdated phone book. Being able to assess the value of knowledge matters in choosing what information to acquire and share. It affects decisions like which subjects to teach at school and how to allocate funds to research projects.

Epistemologists are particularly interested in whether knowledge is more valuable than a mere true opinion. Knowledge and true opinion often have a similar usefulness since both accurately represent reality. For example, if a person wants to go to Larissa, a true opinion about the directions can guide them as effectively as knowledge. Considering this problem, Plato proposed that knowledge is better because it is more stable. Another suggestion focuses on practical reasoning, arguing that people put more trust in knowledge than in mere true opinions when drawing conclusions and deciding what to do. A different response says that knowledge has intrinsic value in addition to instrumental value. This view asserts that knowledge is always valuable, whereas true opinion is only valuable in circumstances where it is useful.

Belief and truth

Beliefs are mental states about what is the case, like believing that snow is white or that God exists. In epistemology, they are often understood as subjective attitudes that affirm or deny a proposition, which can be expressed in a declarative sentence. For instance, to believe that snow is white is to affirm the proposition "snow is white". According to this view, beliefs are representations of what the universe is like. They are stored in memory and retrieved when actively thinking about reality or deciding how to act. A different view understands beliefs as behavioral patterns or dispositions to act rather than as representational items stored in the mind. According to this perspective, to believe that there is mineral water in the fridge is nothing more than a group of dispositions related to mineral water and the fridge. Examples are the dispositions to answer questions about the presence of mineral water affirmatively and to go to the fridge when thirsty. Some theorists deny the existence of beliefs, saying that this concept borrowed from folk psychology oversimplifies much more complex psychological or neurological processes. Beliefs are central to various epistemological debates, which cover their status as a component of propositional knowledge, the question of whether people have control over and responsibility for their beliefs, and the issue of whether beliefs have degrees, called credences.

As propositional attitudes, beliefs are true or false depending on whether they affirm a true or a false proposition. According to the correspondence theory of truth, to be true means to stand in the right relation to the world by accurately describing what it is like. This means that truth is objective: a belief is true if it corresponds to a fact. The coherence theory of truth says that a belief is true if it belongs to a coherent system of beliefs. A result of this view is that truth is relative since it depends on other beliefs. Further theories of truth include pragmatist, semantic, pluralist, and deflationary theories. Truth plays a central role in epistemology as a goal of cognitive processes and an attribute of propositional knowledge.

Justification

In epistemology, justification is a property of beliefs that meet certain norms about what a person should believe. According to a common view, this means that the person has sufficient reasons for holding this belief because they have information that supports it. Another view states that a belief is justified if it is formed by a reliable belief formation process, such as perception. The terms reasonable, warranted, and supported are sometimes used as synonyms of the word justified. Justification distinguishes well-founded beliefs from superstition and lucky guesses. However, it does not guarantee truth. For example, a person with strong but misleading evidence may form a justified belief that is false.

Epistemologists often identify justification as a key component of knowledge. Usually, they are not only interested in whether a person has a sufficient reason to hold a belief, known as propositional justification, but also in whether the person holds the belief because or based on this reason, known as doxastic justification. For example, if a person has sufficient reason to believe that a neighborhood is dangerous but forms this belief based on superstition then they have propositional justification but lack doxastic justification.

Sources

Sources of justification are ways or cognitive capacities through which people acquire justification. Often-discussed sources include perception, introspection, memory, reason, and testimony, but there is no universal agreement to what extent they all provide valid justification. Perception relies on sensory organs to gain empirical information. Distinct forms of perception correspond to different physical stimuli, such as visual, auditory, haptic, olfactory, and gustatory perception. Perception is not merely the reception of sense impressions but an active process that selects, organizes, and interprets sensory signals. Introspection is a closely related process focused on internal mental states rather than external physical objects. For example, seeing a bus at a bus station belongs to perception while feeling tired belongs to introspection.

Rationalists understand reason as a source of justification for non-empirical facts, explaining how people can know about mathematical, logical, and conceptual truths. Reason is also responsible for inferential knowledge, in which one or more beliefs serve as premises to support another belief. Memory depends on information provided by other sources, which it retains and recalls, like remembering a phone number perceived earlier. Justification by testimony relies on information one person communicates to another person. This can happen by talking to each other but can also occur in other forms, like a letter, a newspaper, and a blog.

Other concepts

Rationality is closely related to justification and the terms rational belief and justified belief are sometimes used interchangeably. However, rationality has a wider scope that encompasses both a theoretical side, covering beliefs, and a practical side, covering decisions, intentions, and actions. There are different conceptions about what it means for something to be rational. According to one view, a mental state is rational if it is based on or responsive to good reasons. Another view emphasizes the role of coherence, stating that rationality requires that the different mental states of a person are consistent and support each other. A slightly different approach holds that rationality is about achieving certain goals. Two goals of theoretical rationality are accuracy and comprehensiveness, meaning that a person has as few false beliefs and as many true beliefs as possible.

Epistemologists rely on the concept of epistemic norms as criteria to assess the cognitive quality of beliefs, like their justification and rationality. They distinguish between deontic norms, which prescribe what people should believe, and axiological norms, which identify the goals and values of beliefs. Epistemic norms are closely linked to intellectual or epistemic virtues, which are character traits like open-mindedness and conscientiousness. Epistemic virtues help individuals form true beliefs and acquire knowledge. They contrast with epistemic vices and act as foundational concepts of virtue epistemology.

Epistemologists understand evidence for a belief as information that favors or supports it. They conceptualize evidence primarily in terms of mental states, such as sensory impressions or other known propositions. But in a wider sense, it can also include physical objects, like bloodstains examined by forensic analysts or financial records studied by investigative journalists. Evidence is often understood in terms of probability: evidence for a belief makes it more likely that the belief is true. A defeater is evidence against a belief or evidence that undermines another piece of evidence. For instance, witness testimony linking a suspect to a crime is evidence of their guilt, while an alibi is a defeater. Evidentialists analyze justification in terms of evidence by asserting that for a belief to be justified, it needs to rest on adequate evidence.

The presence of evidence usually affects doubt and certainty, which are subjective attitudes toward propositions that differ regarding their level of confidence. Doubt involves questioning the validity or truth of a proposition. Certainty, by contrast, is a strong affirmative conviction, indicating an absence of doubt about the proposition's truth. Doubt and certainty are central to ancient Greek skepticism and its goal of establishing that no belief is immune to doubt. They are also crucial in attempts to find a secure foundation of all knowledge, such as René Descartes' foundationalist epistemology.

While propositional knowledge is the main topic in epistemology, some theorists focus on understanding instead. Understanding is a more holistic notion that involves a wider grasp of a subject. To understand something, a person requires awareness of how different things are connected and why they are the way they are. For example, knowledge of isolated facts memorized from a textbook does not amount to understanding. According to one view, understanding is a unique epistemic good that, unlike propositional knowledge, is always intrinsically valuable. Wisdom is similar in this regard and is sometimes considered the highest epistemic good. It encompasses a reflective understanding with practical applications, helping people grasp and evaluate complex situations and lead a good life.

In epistemology, knowledge ascription is the act of attributing knowledge to someone, expressed in sentences like "Sarah knows that it will rain today". According to invariantism, knowledge ascriptions have fixed standards across different contexts. Contextualists, by contrast, argue that knowledge ascriptions are context-dependent. From this perspective, Sarah may know about the weather in the context of an everyday conversation even though she is not sufficiently informed to know it in the context of a rigorous meteorological debate. Contrastivism, another view, argues that knowledge ascriptions are comparative, meaning that to know something involves distinguishing it from relevant alternatives. For example, if a person spots a bird in the garden, they may know that it is a sparrow rather than an eagle, but they may not know that it is a sparrow rather than an indistinguishable sparrow hologram.

Major schools of thought

Skepticism and fallibilism

Philosophical skepticism questions the human ability to attain knowledge by challenging the foundations upon which knowledge claims rest. Some skeptics limit their criticism to specific domains of knowledge. For example, religious skeptics say that it is impossible to know about the existence of deities or the truth of other religious doctrines. Similarly, moral skeptics challenge the existence of moral knowledge and metaphysical skeptics say that humans cannot know ultimate reality. External world skepticism questions knowledge of external facts, whereas skepticism about other minds doubts knowledge of the mental states of others.

Global skepticism is the broadest form of skepticism, asserting that there is no knowledge in any domain. In ancient philosophy, this view was embraced by academic skeptics, whereas Pyrrhonian skeptics recommended the suspension of belief to attain tranquility. Few epistemologists have explicitly defended global skepticism. The influence of this position stems from attempts by other philosophers to show that their theory overcomes the challenge of skepticism. For example, René Descartes used methodological doubt to find facts that cannot be doubted.

One consideration in favor of global skepticism is the dream argument. It starts from the observation that, while people are dreaming, they are usually unaware of this. This inability to distinguish between dream and regular experience is used to argue that there is no certain knowledge since a person can never be sure that they are not dreaming. Some critics assert that global skepticism is self-refuting because denying the existence of knowledge is itself a knowledge claim. Another objection says that the abstract reasoning leading to skepticism is not convincing enough to overrule common sense.

Fallibilism is another response to skepticism. Fallibilists agree with skeptics that absolute certainty is impossible. They reject the assumption that knowledge requires absolute certainty, leading them to the conclusion that fallible knowledge exists. They emphasize the need to keep an open and inquisitive mind, acknowledging that doubt can never be fully excluded, even for well-established knowledge claims like thoroughly tested scientific theories.

Epistemic relativism is related to skepticism but differs in that it does not question the existence of knowledge in general. Instead, epistemic relativists only reject the notion of universal epistemic standards or absolute principles that apply equally to everyone. This means that what a person knows depends on subjective criteria or social conventions used to assess epistemic status.

Empiricism and rationalism

Oil painting of a man with gray hair wearing a brown attire
Oil painting showing a man from the front against a dark background, dressed in a red coat with gold embroidery, his left arm resting on a surface
John Locke and David Hume shaped the philosophy of empiricism.

The debate between empiricism and rationalism centers on the origins of human knowledge. Empiricism emphasizes that sense experience is the primary source of all knowledge. Some empiricists illustrate this view by describing the mind as a blank slate that only develops ideas about the external world through the sense data received from the sensory organs. According to them, the mind can attain various additional insights by comparing impressions, combining them, generalizing to form more abstract ideas, and deducing new conclusions from them. Empiricists say that all these mental operations depend on sensory material and do not function on their own.

Even though rationalists usually accept sense experience as one source of knowledge, they argue that certain forms of knowledge are directly accessed through reason without sense experience, like knowledge of mathematical and logical truths. Some forms of rationalism state that the mind possesses inborn ideas, accessible without sensory assistance. Others assert that there is an additional cognitive faculty, sometimes called rational intuition, through which people acquire nonempirical knowledge. Some rationalists limit their discussion to the origin of concepts, saying that the mind relies on inborn categories to understand the world and organize experience.

Foundationalism and coherentism

Diagram with sections for foundationalism, coherentism, and infinitism, each depicting the relations between beliefs
Diagram of foundationalism, coherentism, and infinitism with arrows symbolizing support between beliefs. According to foundationalism, some basic beliefs are justified without support from other beliefs. According to coherentism, justification requires that beliefs mutually support each other. According to infinitism, justification requires that beliefs form infinite support chains.

Foundationalists and coherentists disagree about the structure of knowledge. Foundationalism distinguishes between basic and non-basic beliefs. A belief is basic if it is justified directly, meaning that its validity does not depend on the support of other beliefs. A belief is non-basic if it is justified by another belief. For example, the belief that it rained last night is a non-basic belief if it is inferred from the observation that the street is wet. According to foundationalism, basic beliefs are the foundation on which all other knowledge is built while non-basic beliefs act as the superstructure resting on this foundation.

Coherentists reject the distinction between basic and non-basic beliefs, saying that the justification of any belief depends on other beliefs. They assert that a belief must align with other beliefs to amount to knowledge. This occurs when beliefs are consistent and support each other. According to coherentism, justification is a holistic aspect determined by the whole system of beliefs, which resembles an interconnected web.

Foundherentism is an intermediary position combining elements of both foundationalism and coherentism. It accepts the distinction between basic and non-basic beliefs while asserting that the justification of non-basic beliefs depends on coherence with other beliefs.

Infinitism presents a less common alternative perspective on the structure of knowledge. It agrees with coherentism that there are no basic beliefs while rejecting the view that beliefs can support each other in a circular manner. Instead, it argues that beliefs form infinite justification chains, in which each link of the chain supports the belief following it and is supported by the belief preceding it.

Internalism and externalism

Black and white photo of a bearded man wearing a suit and a tie
Alvin Goldman was an influential defender of externalism.

The disagreement between internalism and externalism is about the sources of justification. Internalists say that justification depends only on factors within the individual, such as perceptual experience, memories, and other beliefs. This view emphasizes the importance of the cognitive perspective of the individual in the form of their mental states. It is commonly associated with the idea that the relevant factors are accessible, meaning that the individual can become aware of their reasons for holding a justified belief through introspection and reflection.

Evidentialism is an influential internalist view, asserting that justification depends on the possession of evidence. In this context, evidence for a belief is any information in the individual's mind that supports the belief. For example, the perceptual experience of rain is evidence for the belief that it is raining. Evidentialists suggest various other forms of evidence, including memories, intuitions, and other beliefs. According to evidentialism, a belief is justified if the individual's evidence supports it and they hold the belief on the basis of this evidence.

Externalism, by contrast, asserts that at least some relevant factors of knowledge are external to the individual. For instance, when considering the belief that a cup of coffee stands on the table, externalists are not primarily interested in the subjective perceptual experience that led to this belief. Instead, they focus on objective factors, like the quality of the person's eyesight, their ability to differentiate coffee from other beverages, and the circumstances under which they observed the cup. A key motivation of many forms of externalism is that justification makes it more likely that a belief is true. Based on this view, justification is external to the extent that some factors contributing to this likelihood are not part of the believer's cognitive perspective.

Reliabilism is an externalist theory asserting that a reliable connection between belief and truth is required for justification. Some reliabilists explain this in terms of reliable processes. According to this view, a belief is justified if it is produced by a reliable process, like perception. A belief-formation process is deemed reliable if most of the beliefs it generates are true. An alternative view focuses on beliefs rather than belief-formation processes, saying that a belief is justified if it is a reliable indicator of the fact it presents. This means that the belief tracks the fact: the person believes it because it is true but would not believe it otherwise.

Virtue epistemology, another type of externalism, asserts that a belief is justified if it manifests intellectual virtues. Intellectual virtues are capacities or traits that perform cognitive functions and help people form true beliefs. Suggested examples include faculties, like vision, memory, and introspection, and character traits, like open-mindedness.

Branches and approaches

Some branches of epistemology are characterized by their research methods. Formal epistemology employs formal tools from logic and mathematics to investigate the nature of knowledge. For example, Bayesian epistemology represents beliefs as degrees of certainty and uses probability theory to formally define norms of rationality governing how certain people should be. Experimental epistemologists base their research on empirical evidence about common knowledge practices. Applied epistemology focuses on the practical application of epistemological principles to diverse real-world problems, like the reliability of knowledge claims on the internet, how to assess sexual assault allegations, and how racism may lead to epistemic injusticeMetaepistemologists study the nature, goals, and research methods of epistemology. As a metatheory, it does not directly advocate for specific epistemological theories but examines their fundamental concepts and background assumptions.

Particularism and generalism disagree about the right method of conducting epistemological research. Particularists start their inquiry by looking at specific cases. For example, to find a definition of knowledge, they rely on their intuitions about concrete instances of knowledge and particular thought experiments. They use these observations as methodological constraints that any theory of general principles needs to follow. Generalists proceed in the opposite direction. They prioritize general epistemic principles, saying that it is not possible to accurately identify and describe specific cases without a grasp of these principles. Other methods in contemporary epistemology aim to extract philosophical insights from ordinary language or look at the role of knowledge in making assertions and guiding actions.

Phenomenological epistemology emphasizes the importance of first-person experience. It distinguishes between the natural and the phenomenological attitudes. The natural attitude focuses on objects belonging to common sense and natural science. The phenomenological attitude focuses on the experience of objects and aims to provide a presuppositionless description of how objects appear to the observer.

Naturalized epistemology is closely associated with the natural sciences, relying on their methods and theories to examine knowledge. Arguing that epistemological theories should rest on empirical observation, it is critical of a priori reasoning. Evolutionary epistemology is a naturalistic approach that understands cognition as a product of evolution, examining knowledge and the cognitive faculties responsible for it through the lens of natural selectionSocial epistemology focuses on the social dimension of knowledge. While traditional epistemology is mainly interested in the knowledge possessed by individuals, social epistemology covers knowledge acquisition, transmission, and evaluation within groups, with specific emphasis on how people rely on each other when seeking knowledge.

Pragmatist epistemology is a form of fallibilism that emphasizes the close relation between knowing and acting. It sees the pursuit of knowledge as an ongoing process guided by common sense and experience while always open to revision. This approach reinterprets some core epistemological notions, for example, by conceptualizing beliefs as habits that shape actions rather than representations that mirror the world. Motivated by pragmatic considerations, epistemic conservatism is a view about belief revision. It prioritizes pre-existing beliefs, asserting that a person should only change their beliefs if they have a good reason to. One argument for epistemic conservatism rests on the recognition that the cognitive resources of humans are limited, making it impractical to constantly reexamine every belief.

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The work of Elizabeth S. Anderson combines the perspectives of feminist, social, and naturalized epistemology.

Postmodern epistemology critiques the conditions of knowledge in advanced societies. This concerns in particular the metanarrative of a constant progress of scientific knowledge leading to a universal and foundational understanding of reality. Similarly, feminist epistemology adopts a critical perspective, focusing on the effect of gender on knowledge. Among other topics, it explores how preconceptions about gender influence who has access to knowledge, how knowledge is produced, and which types of knowledge are valued in society. Some postmodern and feminist thinkers adopt a constructivist approach, arguing that the way people view the world is not a simple reflection of external reality but a social construction. This view emphasizes the creative role of interpretation while undermining objectivity since social constructions can vary across societies. Another critical approach, found in decolonial scholarship, opposes the global influence of Western knowledge systems. It seeks to undermine Western hegemony and decolonize knowledge.

The decolonial outlook is also present in African epistemology. Grounded in African ontology, it emphasizes the interconnectedness of reality as a continuum between knowing subject and known object. It understands knowledge as a holistic phenomenon that includes sensory, emotional, intuitive, and rational aspects, extending beyond the limits of the physical domain.

Another epistemological tradition is found in ancient Indian philosophy. Its diverse schools of thought examine different sources of knowledge, called pramāṇa. Perception, inference, and testimony are sources discussed by most schools. Other sources only considered by some schools are non-perception, which leads to knowledge of absences, and presumption. Buddhist epistemology focuses on immediate experience, understood as the presentation of unique particulars without secondary cognitive processes, like thought and desire. Nyāya epistemology is a causal theory of knowledge, understanding sources of knowledge as reliable processes that cause episodes of truthful awareness. It sees perception as the primary source of knowledge and emphasizes its importance for successful action. Mīmāṃsā epistemology considers the holy scriptures known as the Vedas as a key source of knowledge, addressing the problem of their right interpretation. Jain epistemology states that reality is many-sided, meaning that no single viewpoint can capture the entirety of truth.

Historical epistemology examines how the understanding of knowledge and related concepts has changed over time. It asks whether the main issues in epistemology are perennial and to what extent past epistemological theories are relevant to contemporary debates. It is particularly concerned with scientific knowledge and practices associated with it. It contrasts with the history of epistemology, which presents, reconstructs, and evaluates epistemological theories of philosophers in the past.

Knowledge in particular domains

Some branches of epistemology focus on knowledge within specific academic disciplines. The epistemology of science examines how scientific knowledge is generated and what problems arise in the process of validating, justifying, and interpreting scientific claims. A key issue concerns the problem of how individual observations can support universal scientific laws. Other topics include the nature of scientific evidence and the aims of science. The epistemology of mathematics studies the origin of mathematical knowledge. In exploring how mathematical theories are justified, it investigates the role of proofs and whether there are empirical sources of mathematical knowledge.

Distinct areas of epistemology are dedicated to specific sources of knowledge. Examples are the epistemology of perception, the epistemology of memory, and the epistemology of testimony. In the epistemology of perception, direct and indirect realists debate the connection between the perceiver and the perceived object. Direct realists say that this connection is direct, meaning that there is no difference between the object present in perceptual experience and the physical object causing this experience. According to indirect realism, the connection is indirect, involving mental entities, like ideas or sense data, that mediate between the perceiver and the external world. The contrast between direct and indirect realism is important for explaining the nature of illusions.

Epistemological issues are found in most areas of philosophy. The epistemology of logic examines how people know that an argument is valid. For example, it explores how logicians justify that modus ponens is a correct rule of inference or that all contradictions are false. Epistemologists of metaphysics investigate whether knowledge of the basic structure of reality is possible and what sources this knowledge could have. Knowledge of moral statements, like the claim that lying is wrong, belongs to the epistemology of ethics. It studies the role of ethical intuitions, coherence among moral beliefs, and the problem of moral disagreement. The ethics of belief is a closely related field exploring the intersection of epistemology and ethics. It examines the norms governing belief formation and asks whether violating them is morally wrong. Religious epistemology studies the role of knowledge and justification for religious doctrines and practices. It evaluates the reliability of evidence from religious experience and holy scriptures while also asking whether the norms of reason should be applied to religious faith.

Epistemologists of language explore the nature of linguistic knowledge. One of their topics is the role of tacit knowledge, for example, when native speakers have mastered the rules of grammar but are unable to explicitly articulate them. Epistemologists of modality examine knowledge about what is possible and necessary. Epistemic problems that arise when two people have diverging opinions on a topic are covered by the epistemology of disagreement. Epistemologists of ignorance are interested in epistemic faults and gaps in knowledge.

Epistemology and psychology were not defined as distinct fields until the 19th century; earlier investigations about knowledge often do not fit neatly into today's academic categories. Both contemporary disciplines study beliefs and the mental processes responsible for their formation and change. One key contrast is that psychology describes what beliefs people have and how they acquire them, thereby explaining why someone has a specific belief. The focus of epistemology is on evaluating beliefs, leading to a judgment about whether a belief is justified and rational in a particular case. Epistemology also shares a close connection with cognitive science, which understands mental events as processes that transform informationArtificial intelligence relies on the insights of epistemology and cognitive science to implement concrete solutions to problems associated with knowledge representation and automatic reasoning.

Logic is the study of correct reasoning. For epistemology, it is relevant to inferential knowledge, which arises when a person reasons from one known fact to another. This is the case, for example, when inferring that it rained based on the observation that the streets are wet. Whether an inferential belief amounts to knowledge depends on the form of reasoning used, in particular, that the process does not violate the laws of logic. Another overlap between the two fields is found in the epistemic approach to fallacies. Fallacies are faulty arguments based on incorrect reasoning. The epistemic approach to fallacies explains why they are faulty, stating that arguments aim to expand knowledge. According to this view, an argument is a fallacy if it fails to do so. A further intersection is found in epistemic logic, which uses formal logical devices to study epistemological concepts like knowledge and belief.

Both decision theory and epistemology are interested in the foundations of rational thought and the role of beliefs. Unlike many approaches in epistemology, the main focus of decision theory lies less in the theoretical and more in the practical side, exploring how beliefs are translated into action. Decision theorists examine the reasoning involved in decision-making and the standards of good decisions, identifying beliefs as a central aspect of decision-making. One of their innovations is to distinguish between weaker and stronger beliefs, which helps them consider the effects of uncertainty on decisions.

Epistemology and education have a shared interest in knowledge, with one difference being that education focuses on the transmission of knowledge, exploring the roles of both learner and teacher. Learning theory examines how people acquire knowledge. Behavioral learning theories explain the process in terms of behavior changes, for example, by associating a certain response with a particular stimulusCognitive learning theories study how the cognitive processes that affect knowledge acquisition transform information. Pedagogy looks at the transmission of knowledge from the teacher's perspective, exploring the teaching methods they may employ. In teacher-centered methods, the teacher serves as the main authority delivering knowledge and guiding the learning process. In student-centered methods, the teacher primarily supports and facilitates the learning process, allowing students to take a more active role. The beliefs students have about knowledge, called personal epistemology, influence their intellectual development and learning success.

The anthropology of knowledge examines how knowledge is acquired, stored, retrieved, and communicated. It studies the social and cultural circumstances that affect how knowledge is reproduced and changes, covering the role of institutions like university departments and scientific journals as well as face-to-face discussions and online communications. This field has a broad concept of knowledge, encompassing various forms of understanding and culture, including practical skills. Unlike epistemology, it is not interested in whether a belief is true or justified but in how understanding is reproduced in society. A closely related field, the sociology of knowledge has a similar conception of knowledge. It explores how physical, demographic, economic, and sociocultural factors impact knowledge. This field examines in what sociohistorical contexts knowledge emerges and the effects it has on people, for example, how socioeconomic conditions are related to the dominant ideology in a society.

History

Early reflections on the nature and sources of knowledge are found in ancient history. In ancient Greek philosophy, Plato (427–347 BCE) studied what knowledge is, examining how it differs from true opinion by being based on good reasons. He proposed that learning is a form of recollection in which the soul remembers what it already knew but had forgotten. Plato's student Aristotle (384–322 BCE) was particularly interested in scientific knowledge, exploring the role of sensory experience and the process of making inferences from general principles. Aristotle's ideas influenced the Hellenistic schools of philosophy, which began to arise in the 4th century BCE and included Epicureanism, Stoicism, and skepticism. The Epicureans had an empiricist outlook, stating that sensations are always accurate and act as the supreme standard of judgments. The Stoics defended a similar position but confined their trust to lucid and specific sensations, which they regarded as true. The skeptics questioned that knowledge is possible, recommending instead suspension of judgment to attain a state of tranquility. Emerging in the 3rd century CE and inspired by Plato's philosophy, Neoplatonism distinguished knowledge from true belief, arguing that knowledge is infallible and limited to the realm of immaterial forms.

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The Buddhist philosopher Dharmakirti developed a causal theory of knowledge.

The Upanishads, philosophical scriptures composed in ancient India between 700 and 300 BCE, examined how people acquire knowledge, including the role of introspection, comparison, and deduction. In the 6th century BCE, the school of Ajñana developed a radical skepticism questioning the possibility and usefulness of knowledge. By contrast, the school of Nyaya, which emerged in the 2nd century BCE, asserted that knowledge is possible. It provided a systematic treatment of how people acquire knowledge, distinguishing between valid and invalid sources. When Buddhist philosophers became interested in epistemology, they relied on concepts developed in Nyaya and other traditions. Buddhist philosopher Dharmakirti (6th or 7th century CE) analyzed the process of knowing as a series of causally related events.

Ancient Chinese philosophers understood knowledge as an interconnected phenomenon fundamentally linked to ethical behavior and social involvement. Many saw wisdom as the goal of attaining knowledge. Mozi (470–391 BCE) proposed a pragmatic approach to knowledge using historical records, sensory evidence, and practical outcomes to validate beliefs. Mencius (c. 372–289 BCE) explored analogical reasoning as a source of knowledge and employed this method to criticize Mozi. Xunzi (c. 310–220 BCE) aimed to combine empirical observation and rational inquiry. He emphasized the importance of clarity and standards of reasoning without excluding the role of feeling and emotion.

The relation between reason and faith was a central topic in the medieval period. In Arabic–Persian philosophy, al-Farabi (c. 870–950) and Averroes (1126–1198) discussed how philosophy and theology interact, debating which one is a better vehicle to truth. Al-Ghazali (c. 1056–1111) criticized many core teachings of previous Islamic philosophers, saying that they relied on unproven assumptions that did not amount to knowledge. Similarly in Western philosophy, Anselm of Canterbury (1033–1109) proposed that theological teaching and philosophical inquiry are in harmony and complement each other. Formulating a more critical approach, Peter Abelard (1079–1142) argued against unquestioned theological authorities and said that all things are open to rational doubt. Influenced by Aristotle, Thomas Aquinas (1225–1274) developed an empiricist theory, stating that "nothing is in the intellect unless it first appeared in the senses". According to an early form of direct realism proposed by William of Ockham (c. 1285–1349), perception of mind-independent objects happens directly without intermediaries. Meanwhile, in 14th-century India, Gaṅgeśa developed a reliabilist theory of knowledge and considered the problems of testimony and fallacies. In China, Wang Yangming (1472–1529) explored the unity of knowledge and action, holding that moral knowledge is inborn and can be attained by overcoming self-interest.

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René Descartes used methodological doubt to seek certain foundations for philosophy.

The course of modern philosophy was shaped by René Descartes (1596–1650), who stated that philosophy must begin from a position of indubitable knowledge of first principles. Inspired by skepticism, he aimed to find absolutely certain knowledge by encountering truths that cannot be doubted. He thought that this is the case for the assertion "I think, therefore I am", from which he constructed the rest of his philosophical system. Descartes, together with Baruch Spinoza (1632–1677) and Gottfried Wilhelm Leibniz (1646–1716), belonged to the school of rationalism, which asserts that the mind possesses innate ideas independent of experience. John Locke (1632–1704) rejected this view in favor of an empiricism according to which the mind is a blank slate. This means that all ideas depend on experience, either as "ideas of sense", which are directly presented through the senses, or as "ideas of reflection", which the mind creates by reflecting on its own activities. David Hume (1711–1776) used this idea to explore the limits of what people can know. He said that knowledge of facts is never certain, adding that knowledge of relations between ideas, like mathematical truths, can be certain but contains no information about the world. Immanuel Kant (1724–1804) sought a middle ground between rationalism and empiricism by identifying a type of knowledge overlooked by Hume. For Kant, this knowledge pertains to principles that underlie and structure all experience, such as spatial and temporal relations and fundamental categories of understanding.

In the 19th century and influenced by Kant's philosophy, Georg Wilhelm Friedrich Hegel (1770–1831) rejected empiricism by arguing that sensory impressions alone cannot amount to knowledge since all knowledge is actively structured by the knowing subject. John Stuart Mill (1806–1873), by contrast, defended a wide-sweeping form of empiricism and explained knowledge of general truths through inductive reasoningCharles Peirce (1839–1914) thought that all knowledge is fallible, emphasizing that knowledge seekers should remain open to revising their beliefs in light of new evidence. He used this idea to argue against Cartesian foundationalism, which seeks absolutely certain truths.

In the 20th century, fallibilism was further explored by J. L. Austin (1911–1960) and Karl Popper (1902–1994). In continental philosophy, Edmund Husserl (1859–1938) applied the skeptical idea of suspending judgment to the study of experience. By not judging whether an experience is accurate, he tried to describe its internal structure instead. Influenced by earlier empiricists, logical positivists, like A. J. Ayer (1910–1989), said that all knowledge is either empirical or analytic, rejecting any form of metaphysical knowledge. Bertrand Russell (1872–1970) developed an empiricist sense-datum theory, distinguishing between direct knowledge by acquaintance of sense data and indirect knowledge by description, which is inferred from knowledge by acquaintance. Common sense had a central place in G. E. Moore's (1873–1958) epistemology. He used trivial observations, like the fact that he has two hands, to argue against abstract philosophical theories that deviate from common sense. Ordinary language philosophy, as practiced by the late Ludwig Wittgenstein (1889–1951), is a similar approach that tries to extract epistemological insights from how ordinary language is used.

Edmund Gettier (1927–2021) conceived counterexamples against the idea that knowledge is justified true belief. These counterexamples prompted many philosophers to suggest alternative definitions of knowledge. Developed by philosophers such as Alvin Goldman (1938–2024), reliabilism emerged as one of the alternatives, asserting that knowledge requires reliable sources and shifting the focus away from justification. Virtue epistemologists, such as Ernest Sosa (1940–present) and Linda Zagzebski (1946–present), analyse belief formation in terms of the intellectual virtues or cognitive competencies involved in the process. Naturalized epistemology, as conceived by Willard Van Orman Quine (1908–2000), employs concepts and ideas from the natural sciences to formulate its theories. Other developments in late 20th-century epistemology were the emergence of social, feminist, and historical epistemology.

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