As much as I read about history of philosophy, I saw that a vast majority of ancient philosophers supported determinism(like Cynicists, Stoicists, Buddha etc.).
Did any body support freewill in ancient age?
What was his/her argument?
Philosophy Stack Exchange is a question and answer site for those interested in the study of the fundamental nature of knowledge, reality, and existence. It only takes a minute to sign up.Sign up to join this community
If an argument from Kant is old enough to count (this is implicitly from the Critique of Practical Reason): suppose that you ought not to do something S. Then, if, "You ought to X," implies, "It is possible for you to X," then it is possible for you to not do S. But suppose you end up S'ing. Since actuality implies possibility, it is possible for you to S. But then it was possible for you to S or not: you had a choice. If having a choice is equivalent to having free will, then you have free will. (Note all those "ifs," each controversial!)
Going back farther, https://plato.stanford.edu/entries/freewill/#AnciMediPeri reports:
While Aristotle shares with Plato a concern for cultivating virtues, he gives greater theoretical attention to the role of choice in initiating individual actions which, over time, result in habits, for good or ill. In Book III of the Nicomachean Ethics, Aristotle says that, unlike nonrational agents, we have the power to do or not to do, and much of what we do is voluntary, such that its origin is ‘in us’ and we are ‘aware of the particular circumstances of the action’. Furthermore, mature humans make choices after deliberating about different available means to our ends, drawing on rational principles of action. Choose consistently well (poorly), and a virtuous (vicious) character will form over time, and it is in our power to be either virtuous or vicious.
A question that Aristotle seems to recognize, while not satisfactorily answering, is whether the choice an individual makes on any given occasion is wholly determined by his internal state—perception of his circumstances and his relevant beliefs, desires, and general character dispositions (wherever on the continuum between virtue and vice he may be)—and external circumstances. He says that “the man is the father of his actions as of children”—that is, a person’s character shapes how she acts. One might worry that this seems to entail that the person could not have done otherwise—at the moment of choice, she has no control over what her present character is—and so she is not responsible for choosing as she does. Aristotle responds by contending that her present character is partly a result of previous choices she made. While this claim is plausible enough, it seems to ‘pass the buck’, since ‘the man is the father’ of those earlier choices and actions, too.
No argument is given: our having such choices is just "given."
The article goes on:
Epicurus and his followers had a more mechanistic conception of bodily action than the Stoics. They held that all things (human soul included) are constituted by atoms, whose law-governed behavior fixes the behavior of everything made of such atoms. But they rejected determinism by supposing that atoms, though law-governed, are susceptible to slight ‘swerves’ or departures from the usual paths. Epicurus has often been understood as seeking to ground the freedom of human willings in such indeterministic swerves, but this is a matter of controversy. If this understanding of his aim is correct, how he thought that this scheme might work in detail is not known. (What little we know about his views in this matter stem chiefly from the account given in his follower Lucretius’s six-book poem, On the Nature of Things.)
The argument here, if there is one, appears similar to modern arguments from quantum indeterminism to the possibility of multiple possibilities of outcome in change and, hence, a grounding of some kind for free will (dependent on the relevant definition of such a will).