Dunning–Kruger effect

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect

Relation between average self-perceived performance and average actual performance on a college exam. The red area shows the tendency of low performers to overestimate their abilities. Nevertheless, low performers' self-assessment is lower than that of high performers.

The Dunning–Kruger effect is a cognitive bias that describes the systematic tendency of people with low ability in a specific area to give overly positive assessments of their ability. The term may also refer to the tendency of high performers to underestimate their skills. The effect was formalized and empirically studied by the psychologists David Dunning and Justin Kruger in 1999. In popular culture, the Dunning–Kruger effect is sometimes misunderstood as claiming that people with low intelligence are generally overconfident, instead of denoting specific overconfidence of people unskilled in particular areas.

The original study by Dunning and Kruger focused on logical reasoning, grammar, and social skills. Later, the effect has been demonstrated across multiple studies in a wide range of tasks from fields such as business, politics, medicine, driving, aviation, spatial memory, examinations in school, and literacy. The effect is usually measured by comparing self-assessment with objective performance. For example, participants may take a quiz and estimate their performance afterward, and their estimates are then compared to their actual results.

A number of explanations for, and criticisms of, the Dunning–Kruger effect have been proposed. The metacognitive explanation holds that poor performers misjudge their abilities because they lack the ability to recognize the qualitative difference between their performances and the performances of others. The statistical explanation holds that the empirical effect may largely be the result of a mere statistical effect and the fact that people have a general tendency to think that they are better than average. The rational explanation holds that overly positive prior beliefs about one's skills are the source of false self-assessment. Another explanation claims that self-assessment is more difficult and error-prone for low performers because many of them have very similar skill levels.

There is also disagreement about where the effect applies and about how strong it is, as well as about the practical consequences of the effect. Inaccurate self-assessment could potentially lead low-performers to make poor decisions, such as choosing a career for which they are unfit or engaging in dangerous behavior, or could inhibit them from addressing their shortcomings to improve their competency.

Definition

Not knowing the scope of your own ignorance is part of the human condition. The problem with it is we see it in other people, and we don't see it in ourselves. The first rule of the Dunning–Kruger club is you don't know you're a member of the Dunning–Kruger club.

— David Dunning

The Dunning–Kruger effect is the tendency of people with low ability in a specific area to give overly positive assessments of this ability. This is often seen as a cognitive bias, that is, a systematic tendency to engage in erroneous forms of thinking and judging. In the case of the Dunning–Kruger effect, the systematic error concerns people with low skill in a specific area trying to evaluate their competence within this area and their tendency to greatly overestimate their competence.

The Dunning–Kruger effect is usually defined specifically for the self-assessments of people with a low level of competence. But some theorists do not only restrict it to the bias of people with low skill but also use it to describe the reverse effect, the tendency of highly skilled people to underestimate their abilities relative to the abilities of others. In this case, the source of the error may not be the self-assessment of one's skills, but an overly positive assessment of the skills of others. This phenomenon can be understood as a form of the false-consensus effect, the tendency to "overestimate the extent to which other people share one's beliefs, attitudes, and behaviours".

Some researchers include a metacognitive component in their definition. In this view, the Dunning–Kruger effect is the thesis that those who are incompetent in a given area tend to be ignorant of their incompetence; they lack the metacognitive ability to become aware of their incompetence. As incompetence often includes being unable to tell the difference between competence and incompetence, it is difficult for the incompetent to recognize their incompetence. This is sometimes termed the "dual-burden" account, since low performers are affected by two burdens: they lack a skill and they are unaware of this deficiency. Other definitions focus on the tendency to overestimate one's ability and see the relation to metacognition as a possible explanation that is not part of the definition. This contrast is relevant since the metacognitive explanation is controversial. Many criticisms of the Dunning–Kruger effect target this explanation but accept the empirical findings that low performers tend to overestimate their skills.

Among laypeople, the Dunning–Kruger effect is often misunderstood as the claim that people with low intelligence are more confident in their knowledge and skills than people with high intelligence. According to psychologist Robert D. McIntosh and his colleagues, it is sometimes understood in popular culture as the claim that "stupid people are too stupid to know they are stupid". But the Dunning–Kruger effect applies not to intelligence in general but to skills in specific tasks. Nor does it claim that people lacking a given skill are as confident as high performers. Rather, low performers overestimate themselves but their confidence level is still below that of high performers.

Measurement, analysis, and investigated tasks

Performance at an exam with 45 questions, measured first in relation to the peer group (top) and then in relation to the number of questions answered correctly (bottom). The diagram shows the average performance of the groups corresponding to each quartile.

The most common approach to measuring the Dunning–Kruger effect is to compare self-assessment with objective performance. The self-assessment is sometimes called subjective ability in contrast to the objective ability corresponding to the actual performance. The self-assessment may be done before or after the performance. If done afterward, the participants receive no independent clues during the performance as to how well they did. Thus, if the activity involves answering quiz questions, no feedback is given as to whether a given answer was correct.

The measurement of the subjective and the objective abilities can be in absolute or relative terms. When done in absolute terms, self-assessment and performance are measured according to objective standards, e.g. concerning how many quiz questions were answered correctly. When done in relative terms, the results are compared with a peer group. In this case, participants are asked to assess their performances in relation to the other participants, for example in the form of estimating the percentage of peers they outperformed. The Dunning–Kruger effect is present in both cases, but tends to be significantly more pronounced when done in relative terms; people are usually less accurate when assessing how well they did relative to their peer group than when simply predicting their raw score.

The main point of interest for researchers is usually the correlation between subjective and objective ability. To provide a simplified form of analysis of the measurements, objective performances are often divided into four groups. They start from the bottom quartile of low performers and proceed to the top quartile of high performers. The strongest effect is seen for the participants in the bottom quartile, who tend to see themselves as being part of the top two quartiles when measured in relative terms.

The initial study by David Dunning and Justin Kruger examined the performance and self-assessment of undergraduate students in inductive, deductive, and abductive logical reasoning; English grammar; and appreciation of humor. Across four studies, the research indicates that the participants who scored in the bottom quartile overestimated their test performance and their abilities. Their test scores placed them in the 12th percentile, but they ranked themselves in the 62nd percentile. Other studies focus on how a person's self-view causes inaccurate self-assessments. Some studies indicate that the extent of the inaccuracy depends on the type of task and can be improved by becoming a better performer.

Overall, the Dunning–Kruger effect has been studied across a wide range of tasks, in aviation, business, debating, chess, driving, literacy, medicine, politics, spatial memory, and other fields. Many studies focus on students—for example, how they assess their performance after an exam. In some cases, these studies gather and compare data from different countries. Studies are often done in laboratories; the effect has also been examined in other settings, including assessments of hunters' knowledge of firearms and large Internet surveys.

Explanations

Various theorists have tried to provide models to explain the Dunning–Kruger effect's underlying causes. The original explanation by Dunning and Kruger holds that a lack of metacognitive abilities is responsible. This interpretation is not universally accepted, and many alternative explanations have been proposed. Some of them focus only on one specific factor, while others see a combination of various factors as the cause.

Metacognitive

The metacognitive explanation rests on the idea that part of acquiring a skill consists in learning to distinguish between good and bad performances of the skill. It assumes that people of low skill level are unable to properly assess their performance because they have not yet acquired the discriminatory ability to do so. This leads them to believe that they are better than they actually are because they do not see the qualitative difference between their performance and that of others. In this regard, they lack the metacognitive ability to recognize their incompetence. This model has also been called the "dual-burden account" or the "double-burden of incompetence", since the burden of regular incompetence is paired with the burden of metacognitive incompetence. The metacognitive lack may hinder some people from becoming better by hiding their flaws from them. This can then be used to explain how self-confidence is sometimes higher for unskilled people than for people with an average skill: only the latter are aware of their flaws.

Some attempts have been made to measure metacognitive abilities directly to examine this hypothesis. Some findings suggest that poor performers have reduced metacognitive sensitivity, but it is not clear that its extent is sufficient to explain the Dunning–Kruger effect. Another study concluded that unskilled people lack information but that their metacognitive processes have the same quality as those of skilled people. An indirect argument for the metacognitive model is based on the observation that training people in logical reasoning helps them make more accurate self-assessments. Many criticisms of the metacognitive model hold that it has insufficient empirical evidence and that alternative models offer a better explanation.

Statistical and better-than-average effect

Simulated data of the relation between subjective (self-assessed) and objective IQ. The upper diagram shows the individual data points and the lower one shows the averages of the different IQ groups. This simulation is based only on the statistical effect known as the regression toward the mean together with the better-than-average effect. Proponents of the statistical explanation use it to support their claim that these two factors are sufficient to explain the Dunning–Kruger effect.

A different interpretation is further removed from the psychological level and sees the Dunning–Kruger effect as mainly a statistical artifact. It is based on the idea that the statistical effect known as regression toward the mean explains the empirical findings. This effect happens when two variables are not perfectly correlated: if one picks a sample that has an extreme value for one variable, it tends to show a less extreme value for the other variable. For the Dunning–Kruger effect, the two variables are actual performance and self-assessed performance. If a person with low actual performance is selected, their self-assessed performance tends to be higher.

Most researchers acknowledge that regression toward the mean is a relevant statistical effect that must be taken into account when interpreting the empirical findings. This can be achieved by various methods. Some theorists, like Gilles Gignac and Marcin Zajenkowski, go further and argue that regression toward the mean in combination with other cognitive biases, like the better-than-average effect, can explain most of the empirical findings. This type of explanation is sometimes called "noise plus bias".

According to the better-than-average effect, people generally tend to rate their abilities, attributes, and personality traits as better than average. For example, the average IQ is 100, but people on average think their IQ is 115. The better-than-average effect differs from the Dunning–Kruger effect since it does not track how the overly positive outlook relates to skill. The Dunning–Kruger effect, on the other hand, focuses on how this type of misjudgment happens for poor performers. When the better-than-average effect is paired with regression toward the mean, it shows a similar tendency. This way, it can explain both that unskilled people greatly overestimate their competence and that the reverse effect for highly skilled people is much less pronounced. This can be shown using simulated experiments that have almost the same correlation between objective and self-assessed ability as actual experiments.

Some critics of this model have argued that it can explain the Dunning–Kruger effect only when assessing one's ability relative to one's peer group. But it may not be able to explain self-assessment relative to an objective standard. A further objection claims that seeing the Dunning–Kruger effect as a regression toward the mean is only a form of relabeling the problem and does not explain what mechanism causes the regression.

Based on statistical considerations, Nuhfer et al. arrive at the conclusion that there is no strong tendency to overly positive self-assessment and that the label "unskilled and unaware of it" applies only to few people. Science communicator Jonathan Jarry makes the case that this effect is the only one shown in the original and subsequent papers. Dunning has defended his findings, writing that purely statistical explanations often fail to consider key scholarly findings while adding that self-misjudgements are real regardless of their underlying cause.

Rational

The rational model of the Dunning–Kruger effect explains the observed regression toward the mean not as a statistical artifact but as the result of prior beliefs. If low performers expect to perform well, this can cause them to give an overly positive self-assessment. This model uses a psychological interpretation that differs from the metacognitive explanation. It holds that the error is caused by overly positive prior beliefs and not by the inability to correctly assess oneself. For example, after answering a ten-question quiz, a low performer with only four correct answers may believe they got two questions right and five questions wrong, while they are unsure about the remaining three. Because of their positive prior beliefs, they will automatically assume that they got these three remaining questions right and thereby overestimate their performance.

Distribution of high and low performers

Another model sees the way high and low performers are distributed as the source of erroneous self-assessment. It is based on the assumption that many low performers' skill levels are very similar, i.e., that "many people [are] piled up at the bottom rungs of skill level". This would make it much more difficult for them to accurately assess their skills in relation to their peers. According to this model, the reason for the increased tendency to give false self-assessments is not a lack of metacognitive ability but a more challenging situation in which this ability is applied. One criticism of this interpretation is directed against the assumption that this type of distribution of skill levels can always be used as an explanation. While it can be found in various fields where the Dunning–Kruger effect has been researched, it is not present in all of them. Another criticism holds that this model can explain the Dunning–Kruger effect only when the self-assessment is measured relative to one's peer group, but that it may fail when it is measured relative to absolute standards.

Lack of incentive

A further explanation, sometimes given by theorists with an economic background, focuses on the fact that participants in the corresponding studies lack incentive to give accurate self-assessments. In such cases, intellectual laziness or a desire to look good to the experimenter may motivate participants to give overly positive self-assessments. For this reason, some studies were conducted with additional incentives to be accurate. One study gave participants a monetary reward based on how accurate their self-assessments were. These studies failed to show any significant increase in accuracy for the incentive group in contrast to the control group.

Practical significance

There are disagreements about the Dunning–Kruger effect's magnitude and practical consequences as compared to other psychological effects. Claims about its significance often focus on how it causes affected people to make decisions that have bad outcomes for them or others. For example, according to Gilles E. Gignac and Marcin Zajenkowski, it can have long-term consequences by leading poor performers into careers for which they are unfit. High performers underestimating their skills, though, may forgo viable career opportunities matching their skills in favor of less promising ones that are below their skill level. In other cases, the wrong decisions can also have short-term effects. For example, Pavel et al. hold that overconfidence can lead pilots to operate a new aircraft for which they lack adequate training or to engage in flight maneuvers that exceed their proficiency.

Emergency medicine is another area where the correct assessment of one's skills and the risks of treatment matters. According to Lisa TenEyck, the tendencies of physicians in training to be overconfident must be considered to ensure the appropriate degree of supervision and feedback. Schlösser et al. hold that the Dunning–Kruger effect can also negatively affect economic activities. This is the case, for example, when the price of a good, such as a used car, is lowered by the buyers' uncertainty about its quality. An overconfident buyer unaware of their lack of knowledge may be willing to pay a much higher price because they do not take into account all the potential flaws and risks relevant to the price.

Another implication concerns fields in which researchers rely on people's self-assessments to evaluate their skills. This is common, for example, in vocational counseling or to estimate students' and professionals' information literacy skills. According to Khalid Mahmood, the Dunning–Kruger effect indicates that such self-assessments often do not correspond to the underlying skills. It implies that they are unreliable as a method for gathering this type of data. Regardless of the field in question, the metacognitive ignorance often linked to the Dunning–Kruger effect may inhibit low performers from improving themselves. Since they are unaware of many of their flaws, they may have little motivation to address and overcome them.

Not all accounts of the Dunning–Kruger effect focus on its negative sides. Some also concentrate on its positive sides, e.g., that ignorance is sometimes bliss. In this sense, optimism can lead people to experience their situation more positively, and overconfidence may help them achieve even unrealistic goals. To distinguish the negative from the positive sides, two important phases have been suggested to be relevant for realizing a goal: preparatory planning and the execution of the plan. According to Dunning, overconfidence may be beneficial in the execution phase by increasing motivation and energy. However, it can be detrimental in the planning phase since the agent may ignore bad odds, take unnecessary risks, or fail to prepare for contingencies. For example, being overconfident may be advantageous for a general on the day of battle because of the additional inspiration passed on to his troops. But it can be disadvantageous in the weeks before by ignoring the need for reserve troops or additional protective gear.

Historical precursors of the Dunning–Kruger effect were expressed by theorists such as Charles Darwin ("Ignorance more frequently begets confidence than does knowledge") and Bertrand Russell ("in the modern world the stupid are cocksure while the intelligent are full of doubt"). In 2000, Kruger and Dunning were awarded the satirical Ig Nobel Prize in recognition of the scientific work recorded in "their modest report".

Social equality

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

A pro-marriage equality rally in San Francisco, US

Equality symbol ⊜

Social equality is a state of affairs in which all individuals within society have equal rights, liberties, and status; possibly including civil rights, freedom of expression, autonomy, and equal access to certain public goods and social services.

Social equality requires the absence of legally enforced social class or caste boundaries, along with an absence of discrimination motivated by an inalienable part of an individual's identity. Advocates of social equality believe in equality before the law for all individuals regardless of many aspects. These aspects include but are not limited to, sex, gender, ethnicity, age, sexual orientation, origin, caste or class, income or property, language, religion, convictions, opinions, health, disability, trade union membership, political views, parental status, mores, family or marital status, and any other grounds. These are some different types of social equality:

• Formal equality: equal opportunity for individuals based on merit.
• Substantive equality: equality of outcomes for groups, also called social equity.

Women in Dwarka, New Delhi, line up in protest to get a local liquor shop moved to a different location, away from a school.

Definition

Social equality is variously defined and measured by different schools of thought. These include equality of power, rights, goods, opportunities, capabilities, or some combination of these things. It may also be defined in comparison to distributive equality, power structures between individuals, or justice and political egalitarianism. Societies that promote social equality generally do not make distinctions of rank or social class. In addition to this, interpersonal relationships that exist within a system of social equality are generally based on the idea of mutual respect and equal value rather than hierarchy or honour. Many different ideologies draw from ideas of social equality, including communism, anarchism, multiculturalism, republicanism, democracy, socialism, and social democracy. The advocacy of social equality is egalitarianism. Social equality is distinct from alleviating suffering of the unfortunate in society. It is an expression of the ideal that any two individuals in society should be treated with equal respect and have an equal right to participate in society without regard for social status or hierarchy.

Social equality often pertains to how individuals relate to one another within a society, though it can also be considered in interactions between societies. Social hierarchies may form between states or their citizens when power disparities exist between them, particularly in the context of globalization. These disparities are often distinct in type as well as scope, as citizens in different states do not share a common community or social environment. As advances are made in social equality, both internationally and within a society, the scope of social equality expands as new forms of social inequality become apparent and new solutions become possible.

Historical examples

Illustrating the combat fought in favor of this application on many fronts are the following episodes:

• The Abolitionist Movement (1700s–1800s): Campaigns in Britain, the U.S., and elsewhere fought to end slavery, emphasizing the equal dignity of all humans.
• The Declaration of Independence (1776): Written by Thomas Jefferson; included his famous phrase “all men are created equal,” which became a foundational principle for later equality movements, even though its application was limited at the time.
• The French Revolution (1789): A period of political and societal change in France in view of the abolition of privileges.
• Women's Suffrage Movements (1848–1900s): From the Seneca Falls Convention in 1848 to suffrage victories in Britain and beyond, these movements secured women's right to vote and expanded civic equality.
• The Meiji Reforms in Japan (1868–1912): Abolished feudal hierarchies and introduced legal equality among citizens, modernizing Japanese society.
• Trade Union and Charitable Movements in France (1936 onward): Included labor rights campaigns and charitable initiatives such as those led by Abbé Pierre and the International Movement ATD Fourth World.
• The United Nations (1945 onward): Through its specialized institutions, sought to promote more stable and concrete dialogue and cooperation between its members.
• The Indian Independence Movement (1900s–1947): Gandhi used nonviolent resistance to challenge colonial rule and promote equality.
• The Bandung Conference (1955): Alongside other anti-colonialist movements, reclaimed a better sharing of the world than that realized between great powers at the Yalta Conference.
• The Civil Rights Movement (1950s–1960s): With leaders like Martin Luther King Jr., fought for racial equality and dismantling segregation laws.
• The Anti-Apartheid Movement in South Africa (1948–1994): Led by Nelson Mandela and others, this movement dismantled racial segregation and established equal citizenship.
• Disability Rights Movement (1970s–present): Advocated for equal access, legal protections, and inclusion, culminating in legislation like the Americans with Disabilities Act (1990).
• Microcredit Initiatives (1970s–present): Efforts such as those of Muhammad Yunus promoted equal opportunities by providing financial access to disadvantaged communities.
• LGBTQ+ Rights Movements (1970s–present): Fought for equality in marriage, employment, and social recognition for the LGBTQ+ community.

Philosophical history

Early conceptions of social equality appear in Ancient Greek philosophy. The Stoic philosophers believed that human reason is universal. Plato considered the natures of equality when building society in the Republic, including both a monastic equality and equality in depravity. Aristotle also developed a conception of equality, particularly regarding citizenship, though he rejected the concept of total social equality in favour of social hierarchy. Social equality developed as a practicable element of society in Europe during the Reformation in which traditional religious hierarchies were challenged. The development of post-Reformation political philosophy provided a secular foundation for social equality and political science created empirical systems to analyze social equality in practice.

Social equality was further redefined through the secular and rational philosophies that emerged during The Enlightenment in the 17th and 18th century. Philosophers such as Locke and Rousseau argued that legitimate political authority must rest on the equal rights of citizens, while Montesquieu and Voltaire emphasized equality in governance and freedom of thought. Kant's moral philosophy reinforced the universal dignity of individuals, and Wollstonecraft extended these principles to women, challenging gender hierarchies. These Enlightenment ideas provided the intellectual foundation for modern democratic societies and the expansion of human rights.

The contemporary notion of social equality was developed in the 20th century by political philosophers such as John Rawls, Ronald Dworkin, and Amartya Sen. Rawls defined equality through primary goods like liberty, opportunity, respect, and wealth. Dworkin incorporated a concept of responsibility into Rawls' approach, saying that individuals are personally responsible for voluntary decisions but not natural talents or pre-dispositions. Sen rejected Rawls' measurement of resources in favour of the capability to function. Robert Nozick is known for rejecting Rawls' conception of social equality, arguing that the individual who produced a resource is entitled to it, even if this produces unequal results.

Types

Social equality is a major element of equality for any group in society. Gender equality includes social equality between men, women, and intersex people, whether transgender or cisgender. Historically, women are harmed significantly more by a lack of gender equality, resulting in a higher risk of poverty along with violence, where women across all different countries face abuse or sexual assault. According to the World Health Organization, about every one in every three women face hardships with this. Racial equality and ethnic equality include social equality between people of different races and ethnic origins. Social equality can also be applied to belief and ideology, including equal social status for people of all political or religious beliefs.

The rights of people with disabilities pertain to social equality. Both physical and mental disabilities can prevent individuals from participating in society at an equal level, due to environmental factors as well as stigmas associated with disability. Social equality includes both the treatment of people with disabilities and the accommodation of those to facilitate equal participation in society. Laws are put in place to protect the rights of disabled people such as ADA (Americans with Disabilities Act), which prohibits discrimination in government services, employment, and any public accommodations.

Political and economic equality are commonly overlooked. The ability to participate in the political process is a right that any citizen holds. Movements such as the Voting Rights Act of 1965, and the publications of the 14th and 19th amendment expanded legal protections to insure political equality for all people. While these legal milestones strengthened political rights, true economic equality remains far more complicated. Economic systems often produce unequal access to resources, education, and opportunity, creating gaps that legislation alone cannot fully close. Because of this, the promise of equal participation can feel incomplete when economic barriers still limit many people's ability to thrive or to engage in civic life.

Means

Economic development and industrialization are correlated with increased social equality, along with the idea of an evenly distribution of resources within societies. The industrialization process in which a developing country becomes a developed country corresponds to a significant increase in social equality, and further economic development and growth in developed countries corresponds with further increases in social equality. Education and social equality are also correlated, and increased access to education promotes social equality among individuals.

Other factors have also been correlated with increases in social equality. Access to healthcare and social protection systems is associated with reduced disparities in health and living standards. Democratic participation and civil rights protections are correlated with greater equality in political representation and legal status. Welfare policies and redistributive taxation have been linked to moderation of economic inequality. Together, these correlations suggest that economic development, education, healthcare, and democratic institutions are interconnected with the advancement of social equality.

Standards

Ontological

The standard of equality that states everyone is created equal at birth is called ontological equality. This type of equality can be seen in many places like within Venezuela's Independence day, a day focused on celebrating their adopted Declaration of Independence. Inspired by The United States Declaration of Independence. This early document, which states many of the values of the United States of America, has this idea of equality embedded in it. It says "all men are created equal, that they are endowed by their Creator with certain unalienable Rights". The statement reflects the philosophy of John Locke and his idea that all are equal in terms of certain natural rights.

Opportunity

Main article: Equality of opportunity

Another standard of equality is equality of opportunity, "the idea that everyone has an equal chance to achieve wealth, social prestige, and power because the rules of the game, so to speak, are the same for everyone". This concept can be applied to society by assuming that no one has a head start. This views society almost as a game and any of the differences in equality standards are due to luck and playing the "game" to one's best ability. Formal equality refers to equal opportunity for individuals based on merit while substantive equality reforms to equality of outcomes for groups.

Lesley A. Jacobs, the author of Pursuing Equal Opportunities: The Theory and Practice of Egalitarian Justice, talks about equality of opportunity and its importance relating to egalitarian justice. Jacobs states that: "at the core of equality of opportunity... is the concept that, in competitive procedures designed for the allocation of scarce resources and the distribution of the benefits and burdens of social life, those procedures should be governed by criteria that are relevant to the particular goods at stake in the competition and not by irrelevant considerations such as race, religion, class, gender, disability, sexual orientation, ethnicity, or other factors that may hinder some of the competitors' opportunities at success."

This concept points out factors like race, gender, class, etc. that should not be considered when talking about equality through this notion. Conley also mentions that this standard of equality is at the heart of a bourgeois society, such as a modern capitalist society, or "a society of commerce in which the maximization of profit is the primary business incentive". It was the equal opportunity ideology that civil rights activists adopted in the era of the civil rights movement in the 1960s. This ideology was used by them to argue that Jim Crow laws were incompatible with the standard of equality of opportunity.

Condition

Another notion of equality introduced by Conley is equality of condition. Through this framework is the idea that everyone should have an equal starting point. Conley goes back to his example of a game of Monopoly to explain this standard. If the game of four started with two players both having an advantage of $5,000 to start with and both already owning hotels and other property while the other two players both did not own any property and both started with a $5,000 deficit, then from a perspective of the standard of equality of condition, one can argue that the rules of the game "need to be altered to compensate for inequalities in the relative starting positions". From this policies are formed to even equality which in result bring an efficient way to create fairer competition in society. Here is where social engineering comes into play where society is altered to give an equality of condition to everyone based on race, gender, class, religion, etc. when it is made justifiable that the proponents of the society make it unfair for them.

Sharon E. Kahn, the author of Academic Freedom and the Inclusive University, talks about equality of condition in their work as well and how it correlates to freedom of individuals. Kahn claims that in order to have individual freedom there needs to be equality of condition "which requires much more than the elimination of legal barriers: it requires the creation of a level playing field that eliminates structural barriers to opportunity". Her work refers to academic structure and its problem with equalities and claims that to "ensure equity... we need to recognize that the university structure and its organizational culture have traditionally privileged some and marginalized other; we need to go beyond theoretical concepts of equality by eliminating systemic barriers that hinder the equal participation of members of all groups; we need to create and equality of condition, not merely an equality of opportunity". "Notions of equity, diversity, and inclusiveness begin with a set of premises about individualism, freedom and rights that take as given the existence of deeply rooted inequalities in social structure," therefore in order to have a culture of the inclusive university, it would have to "be based on values of equity; that is, equality of condition" eliminating all systemic barriers that go against equality.

Outcome

Main article: Equality of outcome

The fourth standard of equality is equality of outcome, which is "a position that argues each player must end up with the same amount regardless of the fairness". In this standard of equality, the idea is that "everyone contributes to society and the economy according to what they do best". Under this notion of equality, Conley states that "nobody will earn more power, prestige, and wealth by working harder". Equality of outcome is often falsely conflated with communism or Marxist philosophy, even though these ideologies promote the distribution of resources based on need or contribution (depending on the level of development of a society's productive forces), rather than equality. Vladimir Lenin stated that the "abolition of classes means placing all citizens on an equal footing about the means of production belonging to society as a whole. It means giving all citizens equal opportunities of working on the publicly-owned means of production, on the publicly-owned land, at the publicly-owned factories, and so forth".

When defining equality of outcome in education, "the goals should not be the liberal one of equality of access but equality of outcome for the median number of each identifiable non-educationally defined group, i.e. the average women, negro, or proletarian or rural dweller should have the same level of educational attainment as the average male, white, suburbanite". The outcome and the benefits from equality from education from this notion of equality promotes that all should have the same outcomes and benefits regardless of race, gender, religion etc. The equality of outcome in Hewitt's point of view is supposed to result in "a comparable range of achievements between a specific disadvantaged group – such as an ethnic minority, women, lone parents and the disabled – and society as a whole".

Information ethics is impartial and universal because it brings to ultimate completion the process of enlargement of the concept of what may count as a centre of a (no matter how minimal) moral claim. This now includes every instance of being understood informationally, no matter whether physically implemented or not. In this respect, information ethics holds that every entity, as an expression of being, has a dignity constituted by its mode of existence and essence (the collection of all the elementary properties that constitute it for what it is), which deserve to be respected (at least in a minimal and overridable sense), and hence place moral claims on the interacting agent and ought to contribute to the constraint and guidance of his ethical decisions and behaviour. Floridi goes on to claim that this "ontological equality principle means that any form of reality (any instance of information/being), simply for the fact of being what it is, enjoys a minimal, initial, overridable, equal right to exist and develop in a way which is appropriate to its nature." Values in his claims correlate to those shown in the sociological textbook You May Ask Yourself by Dalton Conley. The notion of "ontological equality" describes equality by saying everything is equal by nature. Everyone is created equal at birth. Everything has an equal right to exist and develop by its nature.

Supramolecular chemistry

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https://en.wikipedia.org/wiki/Supramolecular_chemistry

Supramolecular chemistry is the branch of chemistry concerning chemical systems composed of discrete numbers of molecules. The strength of the forces responsible for spatial organization of the system ranges from weak intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, provided that the electronic coupling strength remains small relative to the energy parameters of the component. While traditional chemistry concentrates on the covalent bond, supramolecular chemistry examines the weaker and reversible non-covalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi–pi interactions and electrostatic effects.

Important concepts advanced by supramolecular chemistry include molecular self-assembly, molecular folding, molecular recognition, host–guest chemistry, mechanically-interlocked molecular architectures, and dynamic covalent chemistry. The study of non-covalent interactions is crucial to understanding many biological processes that rely on these forces for structure and function. Biological systems are often the inspiration for supramolecular research.

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  Self-assembly of a circular double helicate
  
  
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  Host–guest complex within another host (cucurbituril)
  
  
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  Mechanically-interlocked molecules (rotaxane)
  
  
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  An example of a host–guest chemistry
  
  
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  Host–guest complex with a p-xylylenediammonium bound within a cucurbituril
  
  
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  Intramolecular self-assembly of a foldamer
  
  
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  Two pyrene butyric acids bound within a C-hexylpyrogallol[4]arenes nanocapsule. The side chains of the pyrene butyric acids are omitted.
  
  
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  Structure of two isophthalic acids bound to a host molecule through hydrogen bonds
  
  
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  Structure of a short peptide L-Lys-D-Ala-D-Ala (bacterial cell wall precursor) bound to the antibiotic vancomycin

History

18-crown-6 can be synthesized from using potassium ion as the template cation

The existence of intermolecular forces was first postulated by Johannes Diderik van der Waals in 1873. However, Nobel laureate Hermann Emil Fischer developed supramolecular chemistry's philosophical roots. In 1894, Fischer suggested that enzyme–substrate interactions take the form of a "lock and key", the fundamental principles of molecular recognition and host–guest chemistry. In the early twentieth century non-covalent bonds were understood in gradually more detail, with the hydrogen bond being described by Latimer and Rodebush in 1920.

With the deeper understanding of the non-covalent interactions, for example, the clear elucidation of DNA structure, chemists started to emphasize the importance of non-covalent interactions. In 1967, Charles J. Pedersen discovered crown ethers, which are ring-like structures capable of chelating certain metal ions. Then, in 1969, Jean-Marie Lehn discovered a class of molecules similar to crown ethers, called cryptands. After that, Donald J. Cram synthesized many variations to crown ethers, on top of separate molecules capable of selective interaction with certain chemicals. The three scientists were awarded the Nobel Prize in Chemistry in 1987 for "development and use of molecules with structure-specific interactions of high selectivity". In 2016, Bernard L. Feringa, Sir J. Fraser Stoddart, and Jean-Pierre Sauvage were awarded the Nobel Prize in Chemistry, "for the design and synthesis of molecular machines".

 

Carboxylic acid dimers

The term supermolecule (or supramolecule) was introduced by Karl Lothar Wolf et al. (Übermoleküle) in 1937 to describe hydrogen-bonded acetic acid dimers. The term supermolecule is also used in biochemistry to describe complexes of biomolecules, such as peptides and oligonucleotides composed of multiple strands.

Eventually, chemists applied these concepts to synthetic systems. One breakthrough came in the 1960s with the synthesis of the crown ethers by Charles J. Pedersen. Following this work, other researchers such as Donald J. Cram, Jean-Marie Lehn and Fritz Vögtle reported a variety of three-dimensional receptors, and throughout the 1980s research in the area gathered a rapid pace with concepts such as mechanically interlocked molecular architectures emerging.

The influence of supramolecular chemistry was established by the 1987 Nobel Prize for Chemistry which was awarded to Donald J. Cram, Jean-Marie Lehn, and Charles J. Pedersen in recognition of their work in this area. The development of selective "host–guest" complexes in particular, in which a host molecule recognizes and selectively binds a certain guest, was cited as an important contribution.

Concepts

A ribosome is a biological machine that uses protein dynamics on nanoscales.

Molecular self-assembly

Molecular self-assembly is the construction of systems without guidance or management from an outside source (other than to provide a suitable environment). The molecules are directed to assemble through non-covalent interactions. Self-assembly may be subdivided into intermolecular self-assembly (to form a supramolecular assembly), and intramolecular self-assembly (or folding as demonstrated by foldamers and polypeptides). Molecular self-assembly also allows the construction of larger structures such as micelles, membranes, vesicles, liquid crystals, and is important to crystal engineering.

Molecular recognition and complexation

Molecular recognition is the specific binding of a guest molecule to a complementary host molecule to form a host–guest complex. Often, the definition of which species is the "host" and which is the "guest" is arbitrary. The molecules are able to identify each other using non-covalent interactions. Key applications of this field are the construction of molecular sensors and catalysis.

Template-directed synthesis

Molecular recognition and self-assembly may be used with reactive species in order to pre-organize a system for a chemical reaction (to form one or more covalent bonds). It may be considered a special case of supramolecular catalysis. Non-covalent bonds between the reactants and a "template" hold the reactive sites of the reactants close together, facilitating the desired chemistry. This technique is particularly useful for situations where the desired reaction conformation is thermodynamically or kinetically unlikely, such as in the preparation of large macrocycles. This pre-organization also serves purposes such as minimizing side reactions, lowering the activation energy of the reaction, and producing desired stereochemistry. After the reaction has taken place, the template may remain in place, be forcibly removed, or may be "automatically" decomplexed on account of the different recognition properties of the reaction product. The template may be as simple as a single metal ion or may be extremely complex.

Mechanically interlocked molecular architectures

Mechanically interlocked molecular architectures consist of molecules that are linked only as a consequence of their topology. Some non-covalent interactions may exist between the different components (often those that were used in the construction of the system), but covalent bonds do not. Supramolecular chemistry, and template-directed synthesis in particular, is key to the efficient synthesis of the compounds. Examples of mechanically interlocked molecular architectures include catenanes, rotaxanes, molecular knots, molecular Borromean rings, 2D [c2]daisy chain polymer and ravels.

Dynamic covalent chemistry

In dynamic covalent chemistry covalent bonds are broken and formed in a reversible reaction under thermodynamic control. While covalent bonds are key to the process, the system is directed by non-covalent forces to form the lowest energy structures.

Biomimetics

Many synthetic supramolecular systems are designed to copy functions of biological systems. These biomimetic architectures can be used to learn about both the biological model and the synthetic implementation. Examples include photoelectrochemical systems, catalytic systems, protein design and self-replication.

Imprinting

Molecular imprinting describes a process by which a host is constructed from small molecules using a suitable molecular species as a template. After construction, the template is removed leaving only the host. The template for host construction may be subtly different from the guest that the finished host binds to. In its simplest form, imprinting uses only steric interactions, but more complex systems also incorporate hydrogen bonding and other interactions to improve binding strength and specificity.

Molecular machinery

Molecular machines are molecules or molecular assemblies that can perform functions such as linear or rotational movement, switching, and entrapment. These devices exist at the boundary between supramolecular chemistry and nanotechnology, and prototypes have been demonstrated using supramolecular concepts. Jean-Pierre Sauvage, Sir J. Fraser Stoddart and Bernard L. Feringa shared the 2016 Nobel Prize in Chemistry for the 'design and synthesis of molecular machines'.

Building blocks

Supramolecular systems are rarely designed from first principles. Rather, chemists have a range of well-studied structural and functional building blocks that they are able to use to build up larger functional architectures. Many of these exist as whole families of similar units, from which the analog with the exact desired properties can be chosen.

Synthetic recognition motifs

• The pi-pi charge-transfer interactions of bipyridinium with dioxyarenes or diaminoarenes have been used extensively for the construction of mechanically interlocked systems and in crystal engineering.
• The use of crown ether binding with metal or ammonium cations is ubiquitous in supramolecular chemistry.
• The formation of carboxylic acid dimers and other simple hydrogen bonding interactions.
• The complexation of bipyridines or terpyridines with ruthenium, silver or other metal ions is of great utility in the construction of complex architectures of many individual molecules.
• Anion complexation provides a means of linking modules.

Macrocycles

Macrocycles are a traditional component in supramolecular chemistry. The macrocyclic effect enhances otherwise weak interactions. Cyclodextrins, calixarenes, cucurbiturils, and crown ethers allow the incorporation of alkali metal cations. More complex, 3-dimenesion receptors include cyclophanes, and cryptands. Supramolecular metallocycles and metallacrowns are related components. Common metallocycle shapes in these types of applications include triangles, squares, and pentagons, each bearing functional groups that connect the pieces via "self-assembly."

Structural units

Many supramolecular systems require their components to have suitable spacing and conformations relative to each other, and therefore easily employed structural units are required.

• Commonly used spacers and connecting groups include polyether chains, biphenyls and terphenyls, and simple alkyl chains. The chemistry for creating and connecting these units is very well understood.
• nanoparticles, nanorods, fullerenes and dendrimers offer nanometer-sized structure and encapsulation units.
• Surfaces can be used as scaffolds for the construction of complex systems and also for interfacing electrochemical systems with electrodes. Regular surfaces can be used for the construction of self-assembled monolayers and multilayers.
• The understanding of intermolecular interactions in solids has undergone a major renaissance via inputs from different experimental and computational methods in the last decade. This includes high-pressure studies in solids and "in situ" crystallization of compounds which are liquids at room temperature along with the use of electron density analysis, crystal structure prediction and DFT calculations in solid state to enable a quantitative understanding of the nature, energetics and topological properties associated with such interactions in crystals.

Photo-chemically and electro-chemically active units

• Porphyrins, and phthalocyanines have highly tunable photochemical and electrochemical activity as well as the potential to form complexes.
• Photochromic and photoisomerizable groups can change their shapes and properties, including binding properties, upon exposure to light.
• Tetrathiafulvalene (TTF) and quinones have multiple stable oxidation states, and therefore can be used in redox reactions and electrochemistry.
• Other units, such as benzidine derivatives, viologens, and fullerenes, are useful in supramolecular electrochemical devices.

Biologically-derived units

• The extremely strong complexation between avidin and biotin is instrumental in blood clotting, and has been used as the recognition motif to construct synthetic systems.
• The binding of enzymes with their cofactors has been used as a route to produce modified enzymes, electrically contacted enzymes, and even photoswitchable enzymes.
• DNA has been used both as a structural and as a functional unit in synthetic supramolecular systems.

Applications

Supramolecular chemistry per se has found few applications, but underpins some useful phenomena.

Catalysis

Main article: Supramolecular catalysis

The concepts of supramolecular chemistry can inspire the design of catalysts. Non-covalent interactions influence the binding reactants.

Medicine

Design based on supramolecular chemistry has inspired the design of functional biomaterials and therapeutics. Supramolecular biomaterials afford a number of modular and generalizable platforms with tunable mechanical, chemical and biological properties. These include systems based on supramolecular assembly of peptides, host–guest macrocycles, high-affinity hydrogen bonding, and metal–ligand interactions.

A supramolecular approach has been used extensively to create artificial ion channels for the transport of sodium and potassium ions into and out of cells.

Supramolecular interactions influence drug-target binding. In the area of drug delivery, supramolecular chemistry could provide encapsulation and targeted release mechanisms. In addition, supramolecular systems have been designed to disrupt protein–protein interactions that are important to cellular function.

Sensors

Supramolecular interactions have been proposed to detect analytes.