Free will in antiquity is a philosophical and theological concept. 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.Susanne Bobzien, Determinism and Freedom in Stoic Philosophy; Timothy O'Keefe, Epicurus on Freedom, R. W. Sharples, Alexander of Aphrodisias On Fate , David Furley, Two Studies in the Greek Atomists, Richard Sorabji, "Necessity, Cause, and Blame " 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 BC), Aristotle (384–322 BC), Epicurus (341–270 BC), Chrysippus (280–207 BC), and Carneades (214–129 BC).
Ancient Greek philosophy Aristotle
Michael Frede typifies the prevailing view of recent scholarship, namely that Aristotle did not have a notion of free-will.
Aristotle elaborated the four possible causes (material, efficient, formal, and final). Aristotle's word for these causes was ἀιτία, which translates as "causes" in the sense of the multiple factors responsible for an event. Aristotle did not subscribe to the simplistic "every event has a (single) cause" idea that was to come later.
Then, in his Physics and Metaphysics, Aristotle also said there were "accidents" caused by "chance (τυχή)". In his Physics, he noted that the early physicists had found no place for chance among their causes.
Aristotle opposed his accidental chance to necessity: Nor is there any definite cause for an accident, but only chance (τυχόν), namely an indefinite (ἀόριστον) cause.Aristotle, Metaphysics, Book V, 1025a25 It is obvious that there are principles and causes which are generable and destructible apart from the actual processes of generation and destruction; for if this is not true, everything will be of necessity: that is, if there must necessarily be some cause, other than accidental, of that which is generated and destroyed. Will this be, or not? Yes, if this happens; otherwise not.Aristotle, Metaphysics, Book VI, 1027a29
Tracing any particular sequence of events back in time will usually come to an accidental event – a "starting point" or "fresh start" (Aristotle calls it an origin or arche (ἀρχή) – whose major contributing cause (or causes) was itself uncaused.
Whether a particular thing happens, says Aristotle, may depend on a series of causes that goes back to some starting-point, which does not go back to something else. This, therefore, will be the starting-point of the fortuitous, and nothing else is the cause of its generation.Aristotle, Metaphysics Book VI 1027b12-14 In general, many such causal sequences contribute to any event, including human decisions. Each sequence has a different time of origin, some going back before we were born, some originating during our deliberations. Beyond causal sequences that are the result of chance or necessity, Aristotle felt that some breaks in the causal chain allow us to feel our actions "depend on us" (ἐφ' ἡμῖν). These are the causal chains that originate within us (ἐv ἡμῖν).
Richard Sorabji's 1980 Necessity, Cause, and Blame surveyed Aristotle's positions on causation and necessity, comparing them to his predecessors and successors, especially the Stoics and Epicurus. Sorabji argues that Aristotle was an indeterminist, that real chance and uncaused events exist, but never that human actions are uncaused in the extreme libertarian sense that some commentators mistakenly attribute to Epicurus. Aristotle accepted the past as fixed, in the sense that past events were irrevocable. But future events cannot be necessitated by claims about the present truth value of statements about the future. Aristotle does not deny the excluded middle (either p or not p), only that the truth value of p does not exist yet. Indeed, although the past is fixed, the truth value of past statements about the future can be changed by the outcome of future events. This is the problem of future contingents.Richard Sorabji, Necessity, Cause, and Blame, p. ix
Although he thinks Aristotle was not aware of the "problem" of free will vis-a-vis determinism (as first described by Epicurus), Sorabji thinks Aristotle's position on the question is clear enough. Voluntariness is too important to fall before theoretical arguments about necessity and determinism. I come now to the question of how determinism is related to involuntariness. Many commentators nowadays hold one or more parts of the following view. Determinism creates a problem for belief in the voluntariness of actions. Regrettably, but inevitably, Aristotle was unaware of this problem, and so failed to cope with it. Indeed, the problem was not discovered until Hellenistic times, perhaps by Epicurus, who was over forty years junior to Aristotle, and who reached Athens just too late to hear his lectures. In Aristotle's time no one had yet propounded a universal determinism, so that he knew of no such theory. His inevitable failure to see the threat to voluntariness is all the more regrettable in that he himself entertained a deterministic account of actions, which exacerbated the problem of how any could be voluntary. I shall argue that this account misrepresents the situation.Richard Sorabji, Necessity, Cause, and Blame, p. 243
Epicureanism
It is with Epicurus and the Stoics that clearly indeterministic and deterministic positions are first formulated. Writing one generation after Aristotle, Epicurus argued that as atoms moved through the void, there were occasions when they would "swerve" (clinamen) from their otherwise determined paths, thus initiating new causal chains. Epicurus argued that these swerves would allow us to be more responsible for our actions (libertarianism), something impossible if every action was deterministically caused.
Epicurus did not say the swerve was directly involved in decisions. But following Aristotle, Epicurus thought human agents have the autonomous ability to transcend necessity and chance (both of which destroy responsibility), so that praise and blame are appropriate. Epicurus finds a tertium quid (a third option), beyond necessity (Democritus' physics) and beyond Aristotle's chance. His tertium quid is agent autonomy, what is "up to us". Here is the first explicit argument for libertarian free will.
...some things happen of necessity (ἀνάγκη), others by chance (τύχη), others through our own agency (παρ’ ἡμᾶς). ...necessity destroys responsibility and chance is inconstant; whereas our own actions are autonomous, and it is to them that praise and blame naturally attach.Epicurus, Letter to Menoeceus, §133
Lucretius (1st century BCE), a strong supporter of Epicurus, saw the randomness as enabling free will, even if he could not explain exactly how, beyond the fact that random swerves would break the causal chain of determinism. Again, if all motion is always one long chain, and new motion arises out of the old in order invariable, and if the first-beginnings do not make by swerving a beginning of motion such as to break the decrees of fate, that cause may not follow cause from infinity, whence comes this freedom (libera) in living creatures all over the earth, whence I say is this will (voluntas) wrested from the fates by which we proceed whither pleasure leads each, swerving also our motions not at fixed times and fixed places, but just where our mind has taken us? For undoubtedly it is his own will in each that begins these things, and from the will movements go rippling through the limbs.
In 1967, Pamela Huby suggested that Epicurus was the original discoverer of the "free-will problem". Huby noted that there had been two main free-will problems, corresponding to different determinisms, namely theological determinism (predestination and foreknowledge) and the physical causal determinism of Democritus. It is unfortunate that our knowledge of the early history of the Stoics is so fragmentary, and that we have no agreed account of the relations between them and Epicurus. On the evidence we have, however, it seems to me more probable that Epicurus was the originator of the freewill controversy, and that it was only taken up with enthusiasm among the Stoics by Chrysippus, the third head of the school.Pamela Huby, "The First Discovery of the Freewill Problem", Philosophy, 42 (1967), p. 353
In 2000, Susanne Bobzien challenged Pamela Huby's 1967 assertion that Epicurus discovered the "free-will problem". In 1967 Epicurus was credited with the discovery of the problem of free will and determinism. Among the contestants were Aristotle and the early Stoics. Epicurus emerged victorious, because – so the argument went – Aristotle did not yet have the problem, and the Stoics inherited it from Epicurus. In the same year David Furley published his essay 'Aristotle and Epicurus on Voluntary Action', in which he argued that Epicurus' problem was not the free will problem. In the thirty-odd years since then, a lot has been published about Epicurus on freedom and determinism. But it has only rarely been questioned whether Epicurus, in one way or another, found himself face to face with some version of the free will problem. Bobzien thinks Epicurus did not have a model of what she calls "two-sided freedom," because she believes that Epicurus "assumed....a gap in the causal chain immediately before, or simultaneously with, the decision or choice, a gap which allows the coming into being of a spontaneous motion. In this way every human decision or choice is directly linked with causal indeterminism....To avoid misunderstandings, I should stress that I do believe that Epicurus was an indeterminist of sorts – only that he did not advocate indeterminist free decision or indeterminist free choice.
A. A. Long and D. N. Sedley, however, agree with Pamela Huby that Epicurus was the first to notice the modern problem of free will and determinism. Epicurus' problem is this: if it has been necessary all along that we should act as we do, it cannot be up to us, with the result that we would not be morally responsible for our actions at all. Thus posing the problem of determinism he becomes arguably the first philosopher to recognize the philosophical centrality of what we know as the Free Will Question. His strongly libertarian approach to it can be usefully contrasted with the Stoics' acceptance of determinism.Long and Sedley, The Hellenistic Philosophers, section 20, "Free Will," p. 107
The question remains how random swerves can help to explain free action. In her 1992 book, The Hellenistic Philosophy of Mind, Julia Annas wrote: ...since swerves are random, it is hard to see how they help to explain free action. We can scarcely expect there to be a random swerve before every free action. Free actions are frequent, and (fairly) reliable. Random swerves cannot account for either of these features. This problem would be lessened if we could assume that swerves are very frequent, so that there is always likely to be one around before an action. However, if swerves are frequent, we face the problem that stones and trees ought to be enabled to act freely. And even in the case of humans random swerves would seem to produce, if anything, random actions; we still lack any clue as to how they could produce actions which are free.Julia Annas, The Hellenistic Philosophy of Mind, p. 184