Marx's theory of human nature

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https://en.wikipedia.org/wiki/Marx%27s_theory_of_human_nature 

In his works, Karl Marx does not refer to "human nature" as such, but to Gattungswesen, which is generally translated as "species-being" or "species-essence". According to a note from Marx in the Manuscripts of 1844, the term is derived from Ludwig Feuerbach's philosophy, in which it refers both to the nature of each human and of humanity as a whole.

In the sixth Thesis on Feuerbach (1845), Marx criticizes the traditional conception of human nature as a species which incarnates itself in each individual, instead arguing that human nature is formed by the totality of social relations. Marx describes Gattungswesen as neither permanent nor universal, as in classical idealist philosophy, but always determined in a specific social and historical formation, with some aspects being biological.

Background

Philosophers such as Immanuel Kant and Thomas Hobbes believed that humans are naturally selfish, and that it was necessary to constrain human nature in order to achieve a good society. Kant thought rationality ought to be used in achieving this goal, whilst Hobbes placed emphasis on the force of the state. Marxists will argue that this view is an ideological illusion and the effect of commodity fetishism: the fact that people act selfishly is held to be a product of scarcity and capitalism, not an immutable human characteristic.

It is often said that Marx conceived of humans as homo faber, referring to Benjamin Franklin's definition of "man as the tool-making animal" – that is, as "man, the maker", though he never used the term himself.

Writings of Karl Marx

Needs and drives

In the 1844 Manuscripts, the young Marx wrote:

As a natural being and as a living natural being, [Man] is on the one hand endowed with natural powers, vital powers... These forces exist in him as tendencies and abilities – as instincts. On the other hand, as a natural, corporeal, sensuous objective being he is a suffering, conditioned and limited creature, like animals and plants... [T]he objects of his instincts exist outside him, as objects independent of him; yet these objects are objects that he needs... indispensable to the manifestation and confirmation of his essential powers.

In his later works, Marx continues to conceive of human nature as composed of "tendencies", "drives", "essential powers", and "instincts" to act in order to satisfy "needs" for external objectives: Later, in the Grundrisse (1857 – 1858), Marx says his nature is a "totality of needs and drives". In The German Ideology (1846), he uses the formulation: "their needs, consequently their nature".

Basic needs

Some needs are far more important than others. In The German Ideology Marx writes that "life involves before everything else eating and drinking, a habitation, clothing and many other things". All those other aspects of human nature which he discusses (such as "self-activity") are therefore subordinate to the priority given to these. Marx makes explicit his view that humans develop new needs to replace old: "the satisfaction of the first need (the action of satisfying, and the instrument of satisfaction which has been acquired) leads to new needs".

In the 1844 Manuscripts, the young Marx wrote: "It is true that eating, drinking, and procreating, etc., are ... genuine human functions. However, when abstracted from other aspects of human activity, and turned into final and exclusive ends, they are animal."

Social relations and historical materialism

In the sixth of the Theses on Feuerbach, written in 1845, Marx writes that human nature is no more than what is made by social relations: "[T]he essence of man is no abstraction inherent in each single individual. In reality, it is the ensemble of the social relations." Prior, in The Holy Family (1844), Marx argued that capitalists are not motivated by any essential viciousness, but by the drive toward the bare "semblance of a human existence". At around the same time, Marx wrote The German Ideology (1846), in which he wrote that "[a]s individuals express their life, so they are. Hence what individuals are depends on the material conditions of their production".

Later in 1847, Marx wrote The Poverty of Philosophy, stating his belief that human nature conditions the way in which individuals express their lives, against the background of the productive forces and relations of production, at the same time arguing that history involves "a continuous transformation of human nature". In The Communist Manifesto (1848), Marx criticised the tendency to "transform into eternal laws of nature and of reason, the social forms springing from your present mode of production and form of property".

In Capital (1867 – 1894), in a footnote critiquing utilitarianism, he says that utilitarians must reckon with "human nature in general, and then with human nature as modified in each historical epoch".

Labour

Marx's view was that productive activity is an essential human activity, and can be rewarding when pursued freely. However, Marx was always clear that under capitalism, labour was something inhuman, and dehumanising: "[L]abour is external to the worker – i.e., does not belong to his essential being; that he, therefore, does not confirm himself in his work, but denies himself, feels miserable and not happy, does not develop free mental and physical energy, but mortifies his flesh and ruins his mind".

Marx believed that, under communism, "In the individual expression of my life, I would have directly created your expression of your life, and therefore in my individual activity I would have directly confirmed and realised my true nature, my human nature, my communal nature".

Theory of history

Marx's theory of history attempts to describe the way in which humans change their environments and (in dialectical relation) their environments change them as well. That is:

Not only do the objective conditions change in the act of reproduction, e.g. the village becomes a town, the wilderness a cleared field etc., but the producers change, too, in that they bring out new qualities in themselves, develop themselves in production, transform themselves, develop new powers and ideas, new modes of intercourse, new needs and new language.

Further Marx sets out his "materialist conception of history" in opposition to "idealist" conceptions of history, that of Georg Wilhelm Friedrich Hegel, for instance. He writes that "[t]he first premise of all human history is, of course, the existence of living human individuals. Thus the first fact to be established is the physical organisation of these individuals and their consequent relation to the rest of nature." Thus:

History does nothing, it "possesses no immense wealth", it "wages no battles". It is man, real, living man who does all that, who possesses and fights; "history" is not, as it were, a person apart, using man as a means to achieve its own aims; history is nothing but the activity of man pursuing his aims.

Human and animal nature

In several passages throughout his work, Marx shows how he believes humans to be essentially different from other animals, as humans produce their physical environment: "Men can be distinguished from animals by consciousness, by religion or anything else you like. They themselves begin to distinguish themselves from animals as soon as they begin to produce their means of subsistence, a step which is conditioned by their physical organisation." At the same time, Marx notes in Estranged Labour that:

It is true that animals also produce. They build nests and dwellings, like the bee, the beaver, the ant, etc. But they produce only their own immediate needs or those of their young; they produce only when immediate physical need compels them to do so, while man produces even when he is free from physical need and truly produces only in freedom from such need... Animals produce only according to the standards and needs of the species to which they belong, while man is capable of producing according to the standards of every species and of applying to each object its inherent standard; hence, man also produces in accordance with the laws of beauty.

In the same work, Marx writes:

The animal is immediately one with its life activity. It is not distinct from that activity; it is that activity. Man makes his life activity itself an object of his will and consciousness. He has conscious life activity. It is not a determination with which he directly merges. Conscious life activity directly distinguishes man from animal life activity. Only because of that is he a species-being. Or, rather, he is a conscious being – i.e., his own life is an object for him, only because he is a species-being. Only because of that is his activity free activity. Estranged labour reverses the relationship so that man, just because he is a conscious being, makes his life activity, his essential being, a mere means for his existence.

Also in the segment on estranged labour:

Man is a species-being, not only because he practically and theoretically makes the species – both his own and those of other things – his object, but also – and this is simply another way of saying the same thing – because he looks upon himself as the present, living species, because he looks upon himself as a universal and therefore free being.

More than twenty years later, in Capital, he wrote:

A spider conducts operations that resemble those of a weaver, and a bee puts to shame many an architect in the construction of her cells. But what distinguishes the worst architect from the best of bees is this, that the architect raises his structure in imagination before he erects it in reality. At the end of every labour-process, we get a result that already existed in the imagination of the labourer at its commencement. He not only effects a change of form in the material on which he works, but he also realises a purpose of his own that gives the law to his modus operandi, and to which he must subordinate his will. And this subordination is no mere momentary act.

Race

On race, Marx wrote the following:

• "This splendid territory [the Balkans] has the misfortune to be inhabited by a conglomerate of different races and nationalities, of which it is hard to say which is the least fit for progress and civilization. Slavonians, Greeks, Wallachians, Arnauts, twelve millions of men, are all held in submission by one million of Turks, and up to a recent period, it appeared doubtful whether, of all these different races, the Turks were not the most competent to hold the supremacy which, in such a mixed population, could not but accrue to one of these nationalities." Karl Marx, "The Russian Menace to Europe", 1853
• "Russia is a name usurped by the Muscovites. They are not Slavs, do not belong at all to the Indo-German race, but are des intrus [intruders], who must again be hurled back beyond the Dnieper, etc." Karl Marx, letter to Friedrich Engels, June 24, 1865
• "What is the worldly religion of the Jew? Huckstering. What is his worldly God? Money. ... Money is the jealous god of Israel, in face of which no other god may exist. Money degrades all the gods of man—and turns them into commodities. ... The bill of exchange is the real god of the Jew. His god is only an illusory bill of exchange. ... The chimerical nationality of the Jew is the nationality of the merchant, of the man of money in general." Karl Marx, "On the Jewish Question", 1844
• "The expulsion of a Leper people from Egypt, at the head of whom was an Egyptian priest named Moses. Lazarus, the leper, is also the basic type of the Jew." Karl Marx, letter to Friedrich Engels, May 10, 1861
• "Abraham, Isaac and Jacob were fantasy-mongers, that the Israelites were idolators ... that the tribe of Simeon (exiled under Saul) had moved to Mecca where they built a heathenish temple and worshipped stones." Karl Marx, letter to Engels, June 16, 1864

• "The Jewish nigger Lassalle who, I'm glad to say, is leaving at the end of this week, has happily lost another 5,000 talers in an ill-judged speculation. The chap would sooner throw money down the drain than lend it to a 'friend,' even though his interest and capital were guaranteed. ... It is now quite plain to me—as the shape of his head and the way his hair grows also testify—that he is descended from the negroes who accompanied Moses' flight from Egypt (unless his mother or paternal grandmother interbred with a nigger). Now, this blend of Jewishness and Germanness, on the one hand, and basic negroid stock, on the other, must inevitably give rise to a peculiar product. The fellow's importunity is also nigger-like." Karl Marx, "Marx to Friedrich Engels in Manchester", 1862
• Tremaux "proved that the common Negro type is the degenerate form of a much higher one ... a very significant advance over Darwin." Karl Marx, letter to Friedrich Engels, August 7, 1866
• "Indian society has no history at all, at least no known history. What we shall call its history is but the history of the successive invaders who founded their empires on the passive basis of that unresisting and unchanging society." Karl Marx, New York Daily Tribune, August 8, 1853.

Later interpretations

Norman Geras's Marx and Human Nature (1983) is a concise argument against the view that Marx did not believe there was something such as human nature, in particular the confusion surrounding the sixth of the Theses on Feuerbach. Geras offers an argument against Marx's position that social relations determine human nature. He argues that while the social relations are held to "determine" the nature of people, they are not the only such determinant. Geras gives a schedule of some of the needs which Marx says are characteristic of humans:

...for other human beings, for sexual relations, for food, water, clothing, shelter, rest and, more generally, for circumstances that are conducive to health rather than disease. There is another one ... the need of people for a breadth and diversity of pursuit and hence of personal development, as Marx himself expresses these, 'all-round activity', 'all-round development of individuals', 'free development of individuals', 'the means of cultivating [one's] gifts in all directions', and so on.

Geras said of Marx's work that: "Whatever else it is, theory and socio-historical explanation, and scientific as it may be, that work is a moral indictment resting on the conception of essential human needs, an ethical standpoint, in other words, in which a view of human nature is involved."

As regards Marx's theory of human nature against the nature of animals, Allen Wood argues that what is involved in making one's species one's object is more complicated.

Historical materialism

According to Marx, the expansion of the productive forces is itself the fundamental driving force of history. Some writers believe that it is Marx's conception of human nature which explains the "development thesis" concerning this "development thesis".

In his article, "Reconsidering Historical Materialism", however, Cohen gives an argument to the effect that human nature cannot be the premise on which the plausibility of the expansion of the productive forces is grounded:

Production in the historical anthropology is not identical with production in the theory of history. According to the anthropology, people flourish in the cultivation and exercise of their manifold powers, and are especially productive - which in this instance means creative - in the condition of freedom conferred by material plenty. But, in the production of interest to the theory of history, people produce not freely but because they have to, since nature does not otherwise supply their wants; and the development in history of the productive power of man (that is, of man as such, of man as a species) occurs at the expense of the creative capacity of the men who are agents and victims of that development.

The implication of this is that hence "one might ... imagine two kinds of creature, one whose essence it was to create and the other not, undergoing similarly toilsome histories because of similarly adverse circumstances. In one case, but not the other, the toil would be a self-alienating exercise of essential powers". Hence, "historical materialism and Marxist philosophical anthropology are independent of, though also consistent with, each other". Cohen, however, argues that human nature (and other "asocial premises") were sufficient for the development of the productive forces – it could be that they are only one necessary constituent. By 1988, Cohen appears to have considered that the problem was resolved.

Analytical Marxism

One important criticism of Marx's "philosophical anthropology" is offered by G.A. Cohen, the leader of analytical Marxism, in "Reconsidering Historical Materialism" (in Callinicos, ed., 1989). Cohen claims:

Marxist philosophical anthropology is one sided. Its conception of human nature and human good overlooks the need for self-identity than which nothing is more essentially human... Marx and his followers have underestimated the importance of phenomena, such as religion and nationalism, which satisfy the need for self-identity... In his anti-Hegelian, Feuerbachian affirmation of the radical objectivity of matter, Marx focused on the relationship of the subject to an object which is in no way subject, and, as time went on, he came to neglect the subject's relationship to itself, and that aspect of the subject's relationship to others which is a mediated (that is, indirect), form of relationship to itself.

Cohen believes that people are driven, typically, not to create identity, but to preserve that which they have in virtue, for example, of "nationality, or race, or religion, or some slice or amalgam thereof". Cohen does not claim that "Marx denied that there is a need for self-definition, but [instead claims that] he failed to give the truth due emphasis." Nor does Cohen say that the sort of self-understanding that can be found through religion etc. is accurate. Of nationalism, he says "identifications [can] take benign, harmless, and catastrophically malignant forms" and does not believe "that the state is a good medium for the embodiment of nationality".

In Cohen's Karl Marx's Theory of History (1978), he argues that human nature is necessary to explain the development of the productive forces, which Marx holds to drive history. This basic view is endorsed by Geras (1983) and (Wood 2004). The view, however, was criticised by Erik Olin Wright and Andrew Levine in an article entitled Rationality and Class Struggle, first published in the New Left Review. It can be found as chapter 1 of Marxist Theory (ed. Alex Callinicos, 1989). It was also criticised by Joshua Cohen, in a review of KMTH in the Journal of Philosophy.

G.A. Cohen draws out some difficulties with his own presentation in KMTH in the article "Reconsidering Historical Materialism". (First published 1983 in Marxism: NOMOS XXVI, ed. Chapman and Pennock; now available in Marxist Theory ed. Alex Callinicos, 1989; and in History, Labour, and Freedom, G.A. Cohen, 1988).

Post-capitalism

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Post-capitalism 

Post-capitalism is in part a hypothetical state in which the economic systems of the world can no longer be described as forms of capitalism. Various individuals and political ideologies have speculated on what would define such a world. According to classical Marxist and social evolutionary theories, post-capitalist societies may come about as a result of spontaneous evolution as capitalism becomes obsolete. Others propose models to intentionally replace capitalism, most notably socialism, communism, anarchism, nationalism and degrowth.

History

In 1993, Peter Drucker outlined a possible evolution of capitalistic society in his book Post-Capitalist Society.

In 1993, Peter Drucker outlined a possible evolution of capitalistic society in his book Post-Capitalist Society. This states that knowledge, rather than capital, land, or labor, is the new basis of wealth. The classes of a fully post-capitalist society are expected to be divided into knowledge workers or service workers, in contrast to the capitalists and proletarians of a capitalist society. Drucker estimated the transformation to post-capitalism would be completed in 2010–2020. Drucker also argued for rethinking the concept of intellectual property by creating a universal licensing system.

In 2015, according to Paul Mason, several factors — the rise of income inequality, repeating cycles of boom and bust, and capitalism's contributions to climate change — led economists, political thinkers and philosophers to start seriously considering how a post-capitalistic society would look and function. Post-capitalism is expected to be made possible with further advances in automation and information technology – both of which are effectively causing production costs to trend toward zero.

Nick Srnicek and Alex Williams identify a crisis in capitalism's ability and willingness to employ all members of society, arguing that: "there is a growing population of people that are situated outside formal, waged work, with minimal welfare benefits, informal subsistence work, or by illegal means".

Variations

Heritage check system

Main article: For Us, The Living: A Comedy of Customs

Robert Heinlein

Heritage check system is a socioeconomic plan that retains a market economy but removes fractional reserve lending power from banks and limits government printing of money to offset deflation. Money printed is used to buy materials to back the currency and pay for government programs in lieu of taxes, with the remainder to be split evenly among all citizens to stimulate the economy (termed a "heritage check", for which the system is named). The original author of the idea, Robert Heinlein, stated in his book For Us, The Living: A Comedy of Customs, that the system would be self-reinforcing and would eventually result in regular heritage checks able to provide a modest living for most citizens.

Economic democracy

Economic democracy is a socioeconomic philosophy that establishes democratic control of firms by their workers and social control of investment by a network of public banks.

Participatory economy

Main article: Participatory economy

In his book Of the People, By the People: The Case for a Participatory Economy, Robin Hahnel describes a post-capitalist economy called the participatory economy.

Hahnel argues that a participatory economy will return empathy to our purchasing choices. Capitalism removes the knowledge of how and by whom a product was made: "When we eat a salad the market systematically deletes information about the migrant workers who picked it".

Socialism

Main article: Socialism

Paul Mason

Michael Albert

Socialism often implies common ownership of companies and a planned economy, though as an inherently pluralistic ideology, it is argued whether either are essential features. In his book PostCapitalism: A Guide to our Future, Paul Mason argues that centralized planning, even with the advanced technology of today, is unachievable.

In UK politics, strands of Corbynism and the Labour party have adopted this 'post-capitalist' tendency.

Permaculture

Main article: Permaculture

Permaculture is defined by its co-originator Bill Mollison as: "The conscious design and maintenance of agriculturally productive systems which have the diversity, stability, and resilience of natural ecosystems".

PROUT

Main article: Progressive utilization theory

Progressive utilization theory (PROUT) is a socioeconomic and political philosophy created by the Indian philosopher and spiritual leader Prabhat Ranjan Sarkar in 1959. PROUT includes the decentralization of the economy; economic democracy; development of cooperatives; provision of all working members of society with five basic needs: food, clothing, shelter, education, medical care; and systematic solution of environmental problems through technological development and limitation of consumption.

Agrowth

Agrowth ("agnostic or atheistic about growth") is a concept in economic policy according to which it is preferable to be indifferent to the growth of gross domestic product (GDP growth) when devising policies to further economic and societal progress. The reasoning behind agrowth is that GDP growth does not correlate closely with such progress.

The concept has been particularly discussed in the context of environmental policy, where it is opposed to both green growth and degrowth. Agrowth is supported by many scientists.

For example environmental economist Jeroen C. J. M. van den Bergh argues for an agnostic attitude toward economic growth. According to him, environmental policy should not be aimed at pursuing or avoiding growth in the hope of reducing environmental damage, but at direct deployment of effective instruments such as pricing externalities (for example, via environmental taxes or emission rights). Whether the economy grows, stagnates or shrinks as a result is of secondary importance.

Post-growth

Post-growth is an umbrella term that refers to a broad family of economic, ecological, and political perspectives responding to the limits-to-growth dilemma —the recognition that infinite economic growth is biophysically unsustainable on a finite planet. Central to post-growth thinking is the shift of the focus out of GDP growth as the main goal of the economy. Instead, well-being becomes the main objective. Post-growth puts emphasis on decoupling societal well-being from economic growth, advocating for the possibility of prosperity beyond growth.

Scholars define post-growth in different ways. Some describe it as comprising two main categories: degrowth (a stance advocating for a deliberate and equitable reduction in material consumption and economic activity) and agrowth (an agnostic stance towards economic growth, holding that policymakers should remain neutral about GDP growth because it may have either positive or negative effects on environmental or social objectives). According to others it serves as an umbrella term encompassing research in Doughnut and wellbeing economics, steady-state economics, and degrowth.

A systematic review of academic literature found that the distinction between degrowth and post-growth is often unclear, with many authors using post-growth as a catch-all term to avoid the strong connotations associated with degrowth.

Steady-state economy

A steady-state economy is an economy made up of a constant stock of physical wealth (capital) and a constant population size. In effect, such an economy does not grow in the course of time. The term usually refers to the national economy of a particular country, but it is also applicable to the economic system of a city, a region, or the entire world. Early in the history of economic thought, classical economist Adam Smith of the 18th century developed the concept of a stationary state of an economy: Smith believed that any national economy in the world would sooner or later settle in a final state of stationarity.

Since the 1970s, the concept of a steady-state economy has been associated mainly with the work of leading ecological economist Herman Daly. As Daly's concept of a steady-state includes the ecological analysis of natural resource flows through the economy, his concept differs from the original classical concept of a stationary state. One other difference is that Daly recommends immediate political action to establish the steady-state economy by imposing permanent government restrictions on all resource use, whereas economists of the classical period believed that the final stationary state of any economy would evolve by itself without any government intervention.

Critics of the steady-state economy usually object to it by arguing that resource decoupling, technological development, and the operation of market mechanisms are capable of overcoming resource scarcity, pollution, or population overshoot. On the other hand, proponents of the steady-state economy maintain that these objections remain insubstantial and mistaken, and that the need for a steady-state economy is becoming more compelling every day.

Degrowth

Degrowth aims to bring about a post-capitalist world through what Anitra Nelson describes as the reframing and recreation of economies so that they "respect the Earth's limits in order to achieve socio-political equity and ecological sustainability.' They note that degrowth is "distinctive within sustainability and justice movements due to a unique emphasis on growth as a driver of unsustainabilities and inequities." As such "Degrowth argues for a radical reduction in production and consumption, greater citizen participation in politics, and more diversity, especially within ecological systems and landscapes, along with a flourishing of creativity, care, and commoning — using renewable energy and materials.

Degrowth and MMT

Jason Hickel at the University of Oxford

Modern monetary theory (MMT) could enhance the degrowth movement in transitioning to a "post-growth, post-capitalist economy", according to economic anthropologist Jason Hickel. Towards this end, he suggests that the power of "the government's role as the issuer of currency" could be utilized to bring the economy back into balance with the natural world while at the same time reducing economic inequality by providing high quality universal basic services, implementing the rapid development of renewable energy infrastructure to completely phase out fossil fuels in a shorter period of time, and establishing a public job guarantee for 30 hours a week at a living wage doing decommodified, socially useful work in the public services sector, and also useful work in renewable energy development and ecosystem restoration. Hickel notes that providing a living wage at 30 hours a week also has the added benefit of shifting income from capital to labor. Furthermore, he adds that taxation can be used to "reduce demand in order to bring resource and energy use down to target levels," and specifically to reduce the purchasing power of the wealthy.

Technology as a driver of post-capitalism

Automation

Technological change that has driven unemployment has historically been due to 'mechanical-muscle' machines, which have reduced the need for human labor. Just as the use of horses for transport and other work was gradually made obsolete by the invention of the automobile, humans' jobs have also been affected throughout history. A modern example of this technological unemployment is the replacement of retail cashiers by self-service checkouts. The invention and development of 'mechanical-mind' processes or 'brain labor' is thought to threaten jobs at an unprecedented scale, with Oxford Professors Carl Benedikt Frey and Michael Osborne estimating that 47% of US jobs are at risk of automation.

Information technology

Post-capitalism is said to be possible due to major changes brought about by information technology in recent years. These changes have blurred the boundaries between work and free time and loosened the relationship between work and wages. Significantly, information is corroding the market's ability to form prices correctly. Information is abundant and information goods are freely replicable. Goods such as music, software or databases do have a production cost, but once made can be copied infinitely. If the normal price mechanism of capitalism prevails, then the price of any good which has essentially no cost of reproduction will fall towards zero. This lack of scarcity of those things is a problem in those models, which try to counter by developing monopolies in the form of giant tech companies to keep information scarce and commercial. But many significant commodities in the digital economy are now free and open-source, such as Linux, Firefox, Wikipedia and Open-source hardware.

Cognitarism

In 2025, early theoretical frameworks such as Cognitarism proposed socio-economic systems where artificial cognition itself, rather than human labour, was positioned as the primary driver of value creation.

Theory of everything

From Wikipedia, the free encyclopedia

en.wikipedia.org/wiki/Theory_of_everything

 

Beyond the Standard Model
Simulated Large Hadron Collider CMS particle detector data depicting a Higgs boson produced by colliding protons decaying into hadron jets and electrons

A theory of everything (TOE) or final theory is a hypothetical coherent theoretical framework of physics containing all physical principles. The scope of the concept of a "theory of everything" varies. The original technical concept referred to unification of the four fundamental interactions: electromagnetism, strong and weak nuclear forces, and gravity. Finding such a theory of everything is one of the major unsolved problems in physics. Numerous popular books apply the words "theory of everything" to more expansive concepts such as predicting everything in the universe from logic alone, complete with discussions on how this is not possible.

Starting with Isaac Newton's unification of terrestrial gravity, responsible for weight, with celestial gravity, responsible for planetary orbits, concepts in fundamental physics have been successively unified. The phenomena of electricity and magnetism were combined by James Clerk Maxwell's theory of electromagnetism and Albert Einstein's theory of relativity explained how they are connected. By the 1930s, Paul Dirac combined relativity and quantum mechanics and, working with other physicists, developed quantum electrodynamics that combines quantum mechanics and electromagnetism. Work on nuclear and particle physics lead to the discovery of the strong nuclear and weak nuclear forces which were combined in the quantum field theory to implemented the Standard Model of physics, a unification of all forces except gravity. The lone fundamental force not built into the Standard Model is gravity. General relativity provides a theoretical framework for understanding gravity across scales from the laboratory to planets to the complete universe, but it has not been successfully unified with quantum mechanics.

General relativity and quantum mechanics have been repeatedly validated in their separate fields of relevance. Since the usual domains of applicability of general relativity and quantum mechanics are so different, most situations require that only one of the two theories be used. The two theories are considered incompatible in regions of extremely small scale – the Planck scale – such as those that exist within a black hole or during the beginning stages of the universe (i.e., the moment immediately following the Big Bang). To resolve the incompatibility, a theoretical framework revealing a deeper underlying reality, unifying gravity with the other three interactions, must be discovered to harmoniously integrate the realms of general relativity and quantum mechanics into a seamless whole: a theory of everything may be defined as a comprehensive theory that, in principle, would be capable of describing all physical phenomena in the universe.

In pursuit of this goal, quantum gravity has become one area of active research. One example is string theory, which evolved into a candidate for the theory of everything, but not without drawbacks (most notably, its apparent lack of currently testable predictions) and controversy. String theory posits that at the beginning of the universe (up to 10⁻⁴³ seconds after the Big Bang), the four fundamental forces were once a single fundamental force. According to string theory, every particle in the universe, at its most ultramicroscopic level (Planck length), consists of varying combinations of vibrating strings (or strands) with preferred patterns of vibration. String theory further claims that it is through these specific oscillatory patterns of strings that a particle of unique mass and force charge is created (that is to say, the electron is a type of string that vibrates one way, while the up quark is a type of string vibrating another way, and so forth). String theory/M-theory proposes six or seven dimensions of spacetime in addition to the four common dimensions for a ten- or eleven-dimensional spacetime.

Name

The scientific use of the term theory of everything occurred in the title of an article by physicist John Ellis in 1986 but it was mentioned by John Henry Schwarz in a conference proceedings in 1985.

Historical antecedents

Antiquity to 19th century

Archimedes was possibly the first philosopher to have described nature with axioms (or principles) and then deduce new results from them. Once Isaac Newton proposed his universal law of gravitation, mathematician Pierre-Simon Laplace suggested that such laws could in principle allow deterministic prediction of the future state of the universe. Any "theory of everything" is similarly expected to be based on axioms and to deduce all observable phenomena from them.

In the late 17th century, Isaac Newton's description of the long-distance force of gravity implied that not all forces in nature result from things coming into contact. Newton's work in his Mathematical Principles of Natural Philosophy dealt with this in a further example of unification, in this case unifying Galileo's work on terrestrial gravity, Kepler's laws of planetary motion and the phenomenon of tides by explaining these apparent actions at a distance under one single law: the law of universal gravitation. Newton achieved the first great unification in physics, and he further is credited with laying the foundations of future endeavors for a grand unified theory.

An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.

— Essai philosophique sur les probabilités by Pierre-Simon Laplace, Introduction. 1814

Modern quantum mechanics implies that uncertainty is inescapable, and thus that Laplace's vision has to be amended: a theory of everything must include gravitation and quantum mechanics. Even ignoring quantum mechanics, chaos theory is sufficient to guarantee that the future of any sufficiently complex mechanical or astronomical system is unpredictable.

In 1820, Hans Christian Ørsted discovered a connection between electricity and magnetism, triggering decades of work that culminated in 1865, in James Clerk Maxwell's theory of electromagnetism, which achieved the second great unification in physics. During the 19th and early 20th centuries, it gradually became apparent that many common examples of forces – contact forces, elasticity, viscosity, friction, and pressure – result from electrical interactions between the smallest particles of matter.

In his experiments of 1849–1850, Michael Faraday was the first to search for a unification of gravity with electricity and magnetism. However, he found no connection.

Early 20th century

In the late 1920s, the then new quantum mechanics showed that the chemical bonds between atoms were examples of (quantum) electrical forces, justifying Dirac's boast that "the underlying physical laws necessary for the mathematical theory of a large part of physics and the whole of chemistry are thus completely known".

After 1915, when Albert Einstein published the theory of gravity (general relativity), the search for a unified field theory combining gravity with electromagnetism began with a renewed interest. In Einstein's day, the strong and the weak forces had not yet been discovered, yet he found the potential existence of two other distinct forces, gravity and electromagnetism, far more alluring. This launched his 40-year voyage in search of the so-called "unified field theory" that he hoped would show that these two forces are really manifestations of one grand, underlying principle. During the last few decades of his life, this ambition alienated Einstein from the rest of mainstream of physics, as the mainstream was instead far more excited about the emerging framework of quantum mechanics. Einstein wrote to a friend in the early 1940s, "I have become a lonely old chap who is mainly known because he doesn't wear socks and who is exhibited as a curiosity on special occasions." Prominent contributors were Gunnar Nordström, Hermann Weyl, Arthur Eddington, David Hilbert, Theodor Kaluza, Oskar Klein (see Kaluza–Klein theory), and most notably, Albert Einstein and his collaborators. Einstein searched in earnest for, but ultimately failed to find, a unifying theory (see Einstein–Maxwell–Dirac equations).

Late 20th century and the nuclear interactions

In the 20th century, the search for a unifying theory was interrupted by the discovery of the strong and weak nuclear forces, which differ both from gravity and from electromagnetism. A further hurdle was the acceptance that in a theory of everything, quantum mechanics had to be incorporated from the outset, rather than emerging as a consequence of a deterministic unified theory, as Einstein had hoped.

Gravity and electromagnetism are able to coexist as entries in a list of classical forces, but for many years it seemed that gravity could not be incorporated into the quantum framework, let alone unified with the other fundamental forces. For this reason, work on unification, for much of the 20th century, focused on understanding the three forces described by quantum mechanics: electromagnetism and the weak and strong forces. The first two were combined in 1967–1968 by Sheldon Glashow, Steven Weinberg, and Abdus Salam into the electroweak force. Electroweak unification is a broken symmetry: the electromagnetic and weak forces appear distinct at low energies because the particles carrying the weak force, the W and Z bosons, have non-zero masses (80.4 GeV/c² and 91.2 GeV/c², respectively), whereas the photon, which carries the electromagnetic force, is massless. At higher energies W bosons and Z bosons can be created easily and the unified nature of the force becomes apparent.

While the strong and electroweak forces coexist under the Standard Model of particle physics, they remain distinct. Thus, the pursuit of a theory of everything remained unsuccessful: neither a unification of the strong and electroweak forces – which Laplace would have called 'contact forces' – nor a unification of these forces with gravitation had been achieved.

Modern physics

A depiction of the cGh cube

 

Depicted as a Venn diagram

Conventional sequence of theories

A theory of everything would unify all the fundamental interactions of nature: gravitation, the strong interaction, the weak interaction, and electromagnetism. Because the weak interaction can transform elementary particles from one kind into another, the theory of everything should also predict all the different kinds of particles possible. The usual assumed path of theories is given in the following graph, where each unification step leads one level up on the graph.

Theory of everything

Quantum gravity

Space Curvature

Electronuclear force (Grand Unified Theory)

Standard model of cosmology

Standard Model of particle physics

Strong interaction SU(3)

Electroweak interaction SU(2) x U(1)Y

Weak interaction SU(2)

Electromagnetism U(1)EM

Electricity

Magnetism

In this graph, electroweak unification occurs at around 100 GeV, grand unification is predicted to occur at 10¹⁶ GeV, and unification of the GUT force with gravity is expected at the Planck energy, roughly 10¹⁹ GeV.

Several Grand Unified Theories (GUTs) have been proposed to unify electromagnetism and the weak and strong forces. Grand unification would imply the existence of an electronuclear force; it is expected to set in at energies of the order of 10¹⁶ GeV, far greater than could be reached by any currently feasible particle accelerator. Although the simplest grand unified theories have been experimentally ruled out, the idea of a grand unified theory, especially when linked with supersymmetry, remains a favorite candidate in the theoretical physics community. Supersymmetric grand unified theories seem plausible not only for their theoretical "beauty", but because they naturally produce large quantities of dark matter, and because the inflationary force may be related to grand unified theory physics (although it does not seem to form an inevitable part of the theory). Yet grand unified theories are clearly not the final answer; both the current Standard Model and all proposed GUTs are quantum field theories which require the problematic technique of renormalization to yield sensible answers. This is usually regarded as a sign that these are only effective field theories, omitting crucial phenomena relevant only at very high energies.

The final step in the graph requires resolving the separation between quantum mechanics and gravitation, often equated with general relativity. Numerous researchers concentrate their efforts on this specific step; nevertheless, no accepted theory of quantum gravity, and thus no accepted theory of everything, has emerged with observational evidence. It is usually assumed that the theory of everything will also solve the remaining problems of grand unified theories.

In addition to explaining the forces listed in the graph, a theory of everything may also explain the status of at least two candidate forces suggested by modern cosmology: an inflationary force and dark energy. Furthermore, cosmological experiments also suggest the existence of dark matter, supposedly composed of fundamental particles outside the scheme of the Standard Model. However, the existence of these forces and particles has not been proven.

String theory and M-theory

Unsolved problem in physics

Is string theory, superstring theory, or M-theory, or some other variant on this theme, a step on the road to a "theory of everything", or just a blind alley?

More unsolved problems in physics

Since the 1990s, some physicists such as Edward Witten believe that 11-dimensional M-theory, which is described in some limits by one of the five perturbative superstring theories, and in another by the maximally-supersymmetric eleven-dimensional supergravity, is the theory of everything. There is no widespread consensus on this issue.

One remarkable property of string/M-theory is that seven extra dimensions are required for the theory's consistency, on top of the four dimensions in our universe. In this regard, string theory can be seen as building on the insights of the Kaluza–Klein theory, in which it was realized that applying general relativity to a 5-dimensional universe, with one space dimension small and curled up, looks from the 4-dimensional perspective like the usual general relativity together with Maxwell's electrodynamics. This lent credence to the idea of unifying gauge and gravity interactions, and to extra dimensions, but did not address the detailed experimental requirements. Another important property of string theory is its supersymmetry, which together with extra dimensions are the two main proposals for resolving the hierarchy problem of the Standard Model, which is (roughly) the question of why gravity is so much weaker than any other force. The extra-dimensional solution involves allowing gravity to propagate into the other dimensions while keeping other forces confined to a 4-dimensional spacetime, an idea that has been realized with explicit stringy mechanisms.

Research into string theory has been encouraged by a variety of theoretical and experimental factors. On the experimental side, the particle content of the Standard Model supplemented with neutrino masses fits into a spinor representation of SO(10), a subgroup of E₈ that routinely emerges in string theory, such as in heterotic string theory or (sometimes equivalently) in F-theory. String theory has mechanisms that may explain why fermions come in three hierarchical generations, and explain the mixing rates between quark generations. On the theoretical side, it has begun to address some of the key questions in quantum gravity, such as resolving the black hole information paradox, counting the correct entropy of black holes and allowing for topology-changing processes. It has also led to many insights in pure mathematics and in ordinary, strongly-coupled gauge theory due to the Gauge/String duality.

In the late 1990s, it was noted that one major hurdle in this endeavor is that the number of possible 4-dimensional universes is incredibly large. The small, "curled up" extra dimensions can be compactified in an enormous number of different ways (one estimate is 10⁵⁰⁰) each of which leads to different properties for the low-energy particles and forces. This array of models is known as the string theory landscape.

One proposed solution is that many or all of these possibilities are realized in one or another of a huge number of universes, but that only a small number of them are habitable. Hence what we normally conceive as the fundamental constants of the universe are ultimately the result of the anthropic principle rather than dictated by theory. This has led to criticism of string theory, arguing that it cannot make useful (i.e., original, falsifiable, and verifiable) predictions and regarding it as a pseudoscience/philosophy. Others disagree, and string theory remains an active topic of investigation in theoretical physics.

Loop quantum gravity

Current research on loop quantum gravity may eventually play a fundamental role in a theory of everything, but that is not its primary aim. Loop quantum gravity also introduces a lower bound on the possible length scales.

There have been recent claims that loop quantum gravity may be able to reproduce features resembling the Standard Model. So far only the first generation of fermions (leptons and quarks) with correct parity properties have been modelled by Sundance Bilson-Thompson using preons constituted of braids of spacetime as the building blocks. However, there is no derivation of the Lagrangian that would describe the interactions of such particles, nor is it possible to show that such particles are fermions, nor that the gauge groups or interactions of the Standard Model are realised. Use of quantum computing concepts made it possible to demonstrate that the particles are able to survive quantum fluctuations.

This model leads to an interpretation of electric and color charge as topological quantities (electric as number and chirality of twists carried on the individual ribbons and colour as variants of such twisting for fixed electric charge).

Bilson-Thompson's original paper suggested that the higher-generation fermions could be represented by more complicated braidings, although explicit constructions of these structures were not given. The electric charge, color, and parity properties of such fermions would arise in the same way as for the first generation. The model was expressly generalized for an infinite number of generations and for the weak force bosons (but not for photons or gluons) in a 2008 paper by Bilson-Thompson, Hackett, Kauffman and Smolin.

Present status

At present, there is no candidate theory of everything that includes the Standard Model of particle physics and general relativity and that, at the same time, is able to calculate the fine-structure constant or the mass of the electron. Most particle physicists expect that the outcome of ongoing experiments – the search for new particles at the large particle accelerators and for dark matter – are needed in order to provide further input for a theory of everything.

Other proposals

The search for a Theory of Everything is hindered by fundamental incompatibility between the noncommutative and discrete operator algebra structures underlying quantum mechanics and the commutative continuous geometric nature of classical spacetime in general relativity. Reconciling the background-independent, diffeomorphism-invariant formulation of gravity with the fixed-background, time-ordered framework of quantum theory raises profound conceptual issues such as the problem of time and quantum measurement. While a fully successful and experimentally confirmed unified field theory remains elusive, several recent proposals have been advanced, each employing distinct mathematical structures and physical assumptions.

Twistor theory, developed by Roger Penrose, reinterprets the structure of spacetime and fundamental particles through complex geometric objects called twistors. Instead of treating spacetime points as fundamental, twistor theory encodes physical fields and particles into complex projective spaces, aiming to unify quantum theory and general relativity in a geometric framework. Twistors provide potential descriptions of massless fields and scattering amplitudes and have influenced modern approaches in mathematical physics and quantum field theory, including advances in scattering amplitude calculations. Twistor theory has not yet yielded a complete unified field theory.

Alain Connes developed a geometric framework known as noncommutative geometry in which spacetime is extended via noncommutative operator algebras. When combined with spectral triples, this approach can reproduce features of the Standard Model, including the Higgs field, from purely geometric data.

Asymptotic safety, a concept developed by Steven Weinberg in 1976 and also known as Quantum Einstein Gravity and nonperturbative renormalizability, suggests that gravity could find a role in quantum theory if its behavior at very high energies becomes stabilized into a nontrivial ultraviolet (UV) fixed point. This form has been studied through functional renormalization group methods and on the lattice, and applied in cosmology, particle physics, black hole physics, and quantum gravity. Whereas overwhelming numerical evidence does exist that such a fixed point does occur in lower-dimensional constructions and in the numerics, a rigorous proof even for four-dimensional spacetime remains to be found.

Arguments against

In parallel to the intense search for a theory of everything, various scholars have debated the possibility of its discovery.

Gödel's incompleteness theorem

A number of scholars claim that Gödel's incompleteness theorem suggests that attempts to construct a theory of everything are bound to fail. Gödel's theorem, informally stated, asserts that any formal theory sufficient to express elementary arithmetical facts and strong enough for them to be proved is either inconsistent (both a statement and its denial can be derived from its axioms) or incomplete, in the sense that there is a true statement that can't be derived in the formal theory.

The Benedictine priest and science writer Stanley Jaki, in his 1966 book The Relevance of Physics, suggested that Gödel's theorem dooms searches for a deterministic "theory of everything" at least as a consistent non-trivial mathematical theory.

Freeman Dyson has stated that "Gödel's theorem implies that pure mathematics is inexhaustible. No matter how many problems we solve, there will always be other problems that cannot be solved within the existing rules. […] Because of Gödel's theorem, physics is inexhaustible too. The laws of physics are a finite set of rules, and include the rules for doing mathematics, so that Gödel's theorem applies to them."

Stephen Hawking originally believed that a theory of everything could be found, but after considering Gödel's Theorem, he concluded that one was not obtainable: "Some people will be very disappointed if there is not an ultimate theory that can be formulated as a finite number of principles. I used to belong to that camp, but I have changed my mind."

Jürgen Schmidhuber (1997) has argued against this view; he asserts that Gödel's theorems are irrelevant for computable physics. In 2000, Schmidhuber explicitly constructed limit-computable, deterministic universes whose pseudo-randomness based on undecidable, Gödel-like halting problems is extremely hard to detect but does not prevent formal theories of everything describable by very few bits of information.

Related critique was offered by Solomon Feferman and others. Douglas S. Robertson offers Conway's game of life as an example: The underlying rules are simple and complete, but there are formally undecidable questions about the game's behaviors. Analogously, it may (or may not) be possible to completely state the underlying rules of physics with a finite number of well-defined laws, but there is little doubt that there are questions about the behavior of physical systems which are formally undecidable on the basis of those underlying laws.

Fundamental limits in accuracy

No physical theory to date is believed to be precisely accurate. Instead, physics has proceeded by a series of "successive approximations" allowing more and more accurate predictions over a wider and wider range of phenomena. Some physicists believe that it is therefore a mistake to confuse theoretical models with the true nature of reality, and hold that the series of approximations will never terminate in the "truth". Einstein himself expressed this view on occasions.

Definition of fundamental laws

There is a philosophical debate within the physics community as to whether a theory of everything deserves to be called the fundamental law of the universe. One view is the hard reductionist position that the theory of everything is the fundamental law and that all other theories that apply within the universe are a consequence of the theory of everything. Another view is that emergent laws, which govern the behavior of complex systems, should be seen as equally fundamental. Examples of emergent laws are the second law of thermodynamics and the theory of natural selection. The advocates of emergence argue that emergent laws, especially those describing complex or living systems are independent of the low-level, microscopic laws. In this view, emergent laws are as fundamental as a theory of everything.

Impossibility of calculation

Weinberg points out that calculating the precise motion of an actual projectile in the Earth's atmosphere is impossible. So how can we know we have an adequate theory for describing the motion of projectiles? Weinberg suggests that we know principles (Newton's laws of motion and gravitation) that work "well enough" for simple examples, like the motion of planets in empty space. These principles have worked so well on simple examples that we can be reasonably confident they will work for more complex examples. For example, although general relativity includes equations that do not have exact solutions, it is widely accepted as a valid theory because all of its equations with exact solutions have been experimentally verified. Likewise, a theory of everything must work for a wide range of simple examples in such a way that we can be reasonably confident it will work for every situation in physics. Difficulties in creating a theory of everything often begin to appear when combining quantum mechanics with the theory of general relativity, as the equations of quantum mechanics begin to falter when the force of gravity is applied to them.