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Incompatibilists agree that determinism leaves no room for free will. As a result, they reject one or both. Uhrwerkszerlegung 01 GW 02.jpg
Incompatibilists agree that determinism leaves no room for free will. As a result, they reject one or both.

Incompatibilism is the view that a deterministic universe is completely at odds with the notion that persons have a free will; that there is a dichotomy between determinism and free will where philosophers must choose one or the other. This view is pursued in at least three ways: libertarians deny that the universe is deterministic, the hard determinists deny that any free will exists, and pessimistic incompatibilists (hard indeterminists) deny both that the universe is determined and that free will exists.

Determinism is the philosophical idea that all events, including moral choices, are determined completely by previously existing causes. Determinism is at times understood to preclude free will because it entails that humans cannot act otherwise than they do. It can also be called hard determinism from this point of view. Hard determinism is a position on the relationship of determinism to free will. The theory holds that the universe is utterly rational because complete knowledge of any given situation assures that unerring knowledge of its future is also possible. Some philosophers suggest variants around this basic definition. Deterministic theories throughout the history of philosophy have sprung from diverse and sometimes overlapping motives and considerations. The opposite of determinism is some kind of indeterminism. Determinism is often contrasted with free will.

Free will ability of agents to make choices free from certain kinds of constraints

Free will is the ability to choose between different possible courses of action unimpeded.

Dichotomy splitting of a whole into exactly two non-overlapping parts; dyadic relations and processes

A dichotomy is a partition of a whole into two parts (subsets). In other words, this couple of parts must be


Incompatibilism is contrasted with compatibilism, which rejects the determinism/free will dichotomy.

Compatibilism is the belief that free will and determinism are mutually compatible and that it is possible to believe in both without being logically inconsistent. Compatibilists believe freedom can be present or absent in situations for reasons that have nothing to do with metaphysics. They define free will as freedom to act according to one's motives without arbitrary hindrance from other individuals or institutions.


Metaphysical libertarianism argues that free will is real and that determinism is false. Such dualism risks an infinite regress however; [1] if any such mind is real, an objection can still be raised using the standard argument against free will[ clarification needed ] that it is shaped by a necessity or chance.[ clarification needed ] Libertarian Robert Kane (among others) presented an alternative model:

Libertarianism (metaphysics)

Libertarianism is one of the main philosophical positions related to the problems of free will and determinism, which are part of the larger domain of metaphysics. In particular, libertarianism, which is an incompatibilist position, argues that free will is logically incompatible with a deterministic universe and that agents have free will, and that, therefore, determinism is false. On of the first clear formulations of libertarianism is found in John Duns Scotus; in theological context metaphysical libertarianism was notably defended by Jesuit authors like Luis de Molina and Francisco Suárez against rather compatibilist Thomist Báñezianism. Other important metaphysical libertarians in the early modern period were René Descartes, George Berkeley, Immanuel Kant, and Thomas Reid. Roderick Chisholm was a prominent defender of libertarianism in the 20th century, and contemporary libertarians include Robert Kane, Peter van Inwagen and Robert Nozick.

Infinite regress

An infinite regress in a series of propositions arises if the truth of proposition P1 requires the support of proposition P2, the truth of proposition P2 requires the support of proposition P3, and so on, ad infinitum.

Robert Kane (editor of the Oxford Handbook of Free Will) is a leading incompatibilist philosopher in favour of free will. Kane seeks to hold persons morally responsible for decisions that involved indeterminism in their process. Critics maintain that Kane fails to overcome the greatest challenge to such an endeavor: "the argument from luck". [2] Namely, if a critical moral choice is a matter of luck (indeterminate quantum fluctuations), then on what grounds can we hold a person responsible for their final action? Moreover, even if we imagine that a person can make an act of will ahead of time, to make the moral action more probable in the upcoming critical moment, this act of 'willing' was itself a matter of luck.

Robert Hilary Kane is an American philosopher. He is Distinguished Teaching Professor of Philosophy at the University of Texas at Austin, and is currently on phased retirement.

Libertarianism in the philosophy of mind is unrelated to the like-named political philosophy. It suggests that we actually do have free will, that it is incompatible with determinism, and that therefore the future is not determined. For example, at this moment, one could either continue reading this article if one wanted, or cease. Under this assertion, being that one could do either, the fact of how the history of the world will continue to unfold is not currently determined one way or the other.

One famous proponent of this view was Lucretius, who asserted that the free will arises out of the random, chaotic movements of atoms, called "clinamen". One major objection to this view is that science has gradually shown that more and more of the physical world obeys completely deterministic laws, and seems to suggest that our minds are just as much part of the physical world as anything else. If these assumptions are correct, incompatibilist libertarianism can only be maintained as the claim that free will is a supernatural phenomenon, which does not obey the laws of nature (as, for instance, maintained by some religious traditions).

Lucretius Roman poet and philosopher

Titus Lucretius Carus was a Roman poet and philosopher. His only known work is the philosophical poem De rerum natura, a didactic work about the tenets and philosophy of Epicureanism, and which is usually translated into English as On the Nature of Things. Lucretius has been credited with originating the concept of the three-age system which was formalised from 1834 by C. J. Thomsen.

Clinamen is the Latin name Lucretius gave to the unpredictable swerve of atoms, in order to defend the atomistic doctrine of Epicurus. In modern English it has come more generally to mean an inclination or a bias.

However, many libertarian view points now rely upon an indeterministic view of the physical universe, under the assumption that the idea of a deterministic, "clockwork" universe has become outdated since the advent of quantum mechanics.[ citation needed ] By assuming an indeterministic universe libertarian philosophical constructs can be proposed under the assumption of physicalism.

There are libertarian view points based upon indeterminism and physicalism, which is closely related to naturalism. [3] A major problem for naturalistic libertarianism is to explain how indeterminism can be compatible with rationality and with appropriate connections between an individual's beliefs, desires, general character and actions. A variety of naturalistic libertarianism is promoted by Robert Kane, [4] [5] who emphasizes that if our character is formed indeterministically (in "self-forming actions"), then our actions can still flow from our character, and yet still be incompatibilistically free.

Alternatively, libertarian view points based upon indeterminism have been proposed without the assumption of naturalism. At the time C. S. Lewis wrote Miracles , [6] quantum mechanics (and physical indeterminism) was only in the initial stages of acceptance, but still Lewis stated the logical possibility that, if the physical world was proved to be indeterministic, this would provide an entry (interaction) point into the traditionally viewed closed system, where a scientifically described physically probable/improbable event could be philosophically described as an action of a non-physical entity on physical reality (noting that, under a physicalist point of view, the non-physical entity must be independent of the self-identity or mental processing of the sentient being). Lewis mentions this only in passing, making clear that his thesis does not depend on it in any way.

Others may use some form of Donald Davidson's anomalous monism to suggest that although the mind is in fact part of the physical world, it involves a different level of description of the same facts, so that although there are deterministic laws under the physical description, there are no such laws under the mental description, and thus our actions are free and not determined. [7]

Hard determinism

Schopenhauer said "Man is free to do what he wills, but he cannot will what he wills" The Hard Determinist says that obviously, then, there is no 'free will' Schopenhauer.jpg
Schopenhauer said "Man is free to do what he wills, but he cannot will what he wills" The Hard Determinist says that obviously, then, there is no 'free will'

Those who reject free will and accept determinism are variously known as "hard determinists", hard incompatibilists, free will skeptics, illusionists, or impossibilists. They believe that there is no 'free will' and that any sense of the contrary is an illusion. [8] Of course, hard determinists do not deny that one has desires, but say that these desires are causally determined by an unbroken chain of prior occurrences. According to this philosophy, no wholly random, spontaneous, mysterious, or miraculous events occur. Determinists sometimes assert that it is stubborn to resist scientifically motivated determinism on purely intuitive grounds about one's own sense of freedom. They reason that the history of the development of science suggests that determinism is the logical method in which reality works.

William James said that philosophers (and scientists) have an "antipathy to chance." [9] Absolute chance, a possible implication of quantum mechanics and the indeterminacy principle, implies a lack of causality.[ citation needed ] This possibility often disturbs those who assume there must be a causal and lawful explanation for all events.

Moral implications

Since many believe that free will is necessary for moral responsibility, this may imply disastrous consequences for their theory of ethics.

As something of a solution to this predicament, it has been suggested that, for the sake of preserving moral responsibility and the concept of ethics, one might embrace the so-called "illusion" of free will. This, despite thinking that free will does not exist according to determinism. Critics argue that this move renders morality merely another "illusion", or else that this move is simply hypocritical.

The Determinist will add that, even if denying free will does mean morality is incoherent, such an unfortunate result has no effect on the truth. Note, however, that hard determinists often have some sort of 'moral system' that relies explicitly on determinism. A Determinist's moral system simply bears in mind that every person's actions in a given situation are, in theory, predicted by the interplay of environment and upbringing. For instance, the Determinist may still punish undesirable behaviours for reasons of behaviour modification or deterrence.

Hard incompatibilism

Hard incompatibilism, like hard determinism, is a type of skepticism about free will. 'Hard incompatibilism' is a term coined by Derk Pereboom to designate the view that both determinism and indeterminism are incompatible with having free will and moral responsibility. [10] Like the hard determinist, the hard incompatibilist holds that if determinism were true, our having free will would be ruled out. But Pereboom argues in addition that if our decisions were indeterministic events, free will would also be precluded. In his view, free will is the control in action required for the desert aspect of moral responsibility—for our deserving to be blamed or punished for immoral actions, and to be praised or rewarded for morally exemplary actions. He contends that if our decisions were indeterministic events, their occurrence would not be in the control of the agent in the way required for such attributions of desert. [11] The possibility for free will that remains is libertarian agent causation, according to which agents as substances (thus not merely as having a role in events) can cause actions without being causally determined to do so. Pereboom argues that for empirical reasons it is unlikely that we are agent causes of this sort, and that as a result, it is likely that we lack free will. [12]

Experimental research

In recent years researchers in the field of experimental philosophy have been working on determining whether ordinary people, who aren't experts in this field, naturally have compatibilist or incompatibilist intuitions about determinism and moral responsibility. [13] Some experimental work has even conducted cross-cultural studies. [14] The debate about whether people naturally have compatibilist or incompatibilist intuitions has not come out overwhelmingly in favor of one view or the other. Still, there has been some evidence that people can naturally hold both views. For instance, when people are presented with abstract cases which ask if a person could be morally responsible for an immoral act when they could not have done otherwise, people tend to say no, or give incompatibilist answers, but when presented with a specific immoral act that a specific person committed, people tend to say that that person is morally responsible for their actions, even if they were determined (that is, people also give compatibilist answers). [15]

See also

Related Research Articles

Indeterminism is the idea that events are not caused, or not caused deterministically.

Hard determinism

Hard determinism is a view on free will which holds that determinism is true, and that it is incompatible with free will, and, therefore, that free will does not exist. Although hard determinism generally refers to nomological determinism, it can also be a position taken with respect to other forms of determinism that necessitate the future in its entirety. Hard determinism is contrasted with soft determinism, which is a compatibilist form of determinism, holding that free will may exist despite determinism. It is also contrasted with metaphysical libertarianism, the other major form of incompatibilism which holds that free will exists and determinism is false.

C. D. Broad English philosopher

Charlie Dunbar Broad, usually cited as C. D. Broad, was an English epistemologist, historian of philosophy, philosopher of science, moral philosopher, and writer on the philosophical aspects of psychical research. He was known for his thorough and dispassionate examinations of arguments in such works as Scientific Thought, published in 1923, The Mind and Its Place in Nature, published in 1925, and An Examination of McTaggart's Philosophy, published in 1933.

Predeterminism is the idea that all events are determined in advance. Predeterminism is the philosophy that all events of history, past, present and future, have been already decided or are already known, including human actions.

Peter van Inwagen is an American analytic philosopher and the John Cardinal O'Hara Professor of Philosophy at the University of Notre Dame. He is also a Research Professor of Philosophy at Duke University each Spring. He previously taught at Syracuse University and earned his PhD from the University of Rochester in 1969 under the direction of Richard Taylor. Van Inwagen is one of the leading figures in contemporary metaphysics, philosophy of religion, and philosophy of action. He was the president of the Society of Christian Philosophers from 2010 to 2013.

Theological determinism is a form of predeterminism which states that all events that happen are pre-ordained, or/and predestined to happen, by a God/gods, or that they are destined to occur given its omniscience. Theological determinism exists in a number of religions, including Jainism, Judaism, Christianity and Islam. It is also supported by proponents of Classical pantheism such as the Stoics and Baruch Spinoza.

The free will theorem of John H. Conway and Simon B. Kochen states that if we have a free will in the sense that our choices are not a function of the past, then, subject to certain assumptions, so must some elementary particles. Conway and Kochen's paper was published in Foundations of Physics in 2006. In 2009 they published a stronger version of the theorem in the Notices of the AMS. Later Kochen elaborated some details.

In philosophy, moral responsibility is the status of morally deserving praise, blame, reward, or punishment for an act or omission performed or neglected in accordance with one's moral obligations. Deciding what counts as "morally obligatory" is a principal concern of ethics.

Frankfurt cases were presented by philosopher Harry Frankfurt in 1969 as counterexamples to the principle of alternate possibilities (PAP), which holds that an agent is morally responsible for an action only if that person could have done otherwise.

Illusionism is a metaphysical theory first propounded by professor Saul Smilansky of the University of Haifa. It holds that people have illusory beliefs about free will. Furthermore, it holds that it is both of key importance and morally right that people not be disabused of these beliefs, because the illusion has benefits both to individuals and to society. Belief in hard incompatibilism, argues Smilansky, removes an individual's basis for a sense of self-worth in his or her own achievements. It is "extremely damaging to our view of ourselves, to our sense of achievement, worth, and self-respect".

Free will in antiquity was not discussed in the same terms as used in the modern free will debates, but historians of the problem have speculated who exactly was first to take positions as determinist, libertarian, and compatibilist in antiquity. There is wide agreement that these views were essentially fully formed over 2000 years ago. Candidates for the first thinkers to form these views, as well as the idea of a non-physical "agent-causal" libertarianism, include Democritus (460–370), Aristotle (384–322), Epicurus (341–270), Chrysippus (280–207), and Carneades (214–129).

Bruce Waller is a contemporary American philosopher notable for his theories about the nature of free will and its implications for human society. In 2016 he is a professor of Philosophy and Religious Studies at Youngstown State University.

Derk Pereboom is the Susan Linn Sage Professor in Philosophy and Ethics at Cornell University, located in Ithaca, New York, USA. He specializes in the areas of free will and moral responsibility, philosophy of mind, philosophy of religion, and in the work of Immanuel Kant. As of 2018, he is the subject co-editor on topics in the philosophy of action for the Stanford Encyclopedia of Philosophy, and he has also written for the encyclopedia.

Peter Ulric Tse is an American cognitive neuroscientist in the Department of Psychological and Brain Sciences, Dartmouth College. He directs the NSF EPSCoR Attention Consortium. He was awarded a Guggenheim Fellowship in 2014.

<i>Das Problem der Willensfreiheit in der neuesten deutschen Philosophie</i> 1902 book by Dr. Leopold Müffelmann

Das Problem der Willensfreiheit in der neuesten deutschen Philosophie is a book written by Dr. Leopold Müffelmann and published in Leipzig in 1902. It is the dissertation of Dr. Leopold Müffelmann who was a jurist and chief executive of the lodge of the Freemason, and summarizes historical viewpoints on the topic of free will with a focus on the common opinion within German philosophy in the early 20th century. The book considers the general ideas towards the problem, namely indeterminism, fatalism and determinism. Müffelmann treats the subject of free will rather objectively, however, it becomes apparent that his view towards the problem of free will is deterministic. In the dissertation Müffelmann argues, that the problem of free will is actually not as important as often claimed by philosophers and that ethical life and thought should not be made dependent upon it.


  1. Libertarian free will asserts that human actions do not have causes and are chosen consciously - i.e. are not random. This begs the question: what causes these actions? Since they can't be chosen at random by, as explained above, this question can be asked for each subsequent answer to it, thus forming an infinite regress. Similarly, in the 20th century, in the Frankfurt's concept of hierarchical mesh. Similarly, G. Strawson (1998, 2004), Free will, Routledge Encyclopedia of Philosophy.
  3. Williams, Peter S. (Summer 2002). "Why Naturalists Should Mind about Physicalism, and Vice Versa". Quodlibet . 4 (2–3).
  4. summary of Kane's views by the Stanford Encyclopedia of Philosophy
  5. Kane, Robert. “Free Will: New Directions for an Ancient Problem.” (2003). In Free Will, Robert Kane (ed.) (2003) Malden, MA: Blackwell
  6. Lewis, C.S. (1947). Miracles. p. 24. ISBN   0-688-17369-1.
  7. Sosa -- Free Mental Causation! (MS Word)
  8. Saul Smilansky, Free Will and Illusion, Oxford, 2000
  9. William James, The Dilemma of Determinism, p.153
  10. Pereboom, Derk (2001). Living without Free Will. Cambridge: Cambridge University Press.
  11. Pereboom, Derk (2014). Free Will, Agency, and Meaning in Life. Oxford: Oxford University Press.
  12. Derk Pereboom, "Defending Hard incompatibilism", Midwest Studies 29 (2005), pp. 228–47.
  13. Eddy Nahmias, Stephen Morris, Thomas Nadelhoffer, and Jason Turner. (forthcoming).Incompatibilism Intuitive?,” Philosophy and Phenomenological Research.
  14. Hagop Sarkissian, Amita Chatterjee, Felipe De Brigard, Joshua Knobe, Shaun Nichols, Smita Sirker (forthcoming)."Is belief in free will a cultural universal?" Mind & Language
  15. Shaun Nichols and Joshua Knobe. (forthcoming).“Moral Responsibility and Determinism: The Cognitive Science of Folk Intuitions.” Archived December 11, 2009, at the Wayback Machine Nous.