Free will is the ability of an agent to make choices freely. Determinism is the idea that every state of affairs is the inevitable consequence of antecedent states of affairs. Freeze will and determinism seem to conflict because if everything happens because it has been caused by something prior, then there is no other possibility for one to act otherwise than as is caused by the antecedent state of affairs. The discussion about free will is significant in part because our concept of moral responsibility relies on this freedom - one cannot hold a person responsible for an action they were compelled to perform. In order for moral responsibility to hold weight, we want to conclude that we have free will. I think that a theory of free will should seek to, among other things, place a justified weight of moral responsibility on any free agent under the circumstances that would allow them to be free. Then, since determinism seems manifest to me, I shall aim to prove that free will can be compatible with it such that we can achieve the end-goal of asserting the moral responsibility of humans.

Hume (1748) argues that free will and determinism are compatible by asserting that freedom requires determinism - without the mechanism of determinism, even if one chooses to take a particular action, that act may not end up being taken, which itself hinders one’s ability to make real choices. He defines determinism by the idea of necessity, which is the inevitability of a particular cause having no other possible effect than the exact consequence which resulted from it. According to this definition, determinism here plays a mechanistic role, allowing agents to make choices as a direct result of choosing to make them. Hume argues that necessity is a fundamental law which arises from the uniformity observable in the operations of nature, where 1) similar objects are conjoined, and 2) the mind infers the one from the appearance of the other. He uses the examples of the history, politics and law of human societies to prove that we implicitly acknowledge this uniformity and causation in our everyday lives. Hence Hume suggests that determinism plays the role of merely facilitating the operations of nature, while the agent possesses the free will to set those operations into motion.

But the incompatibilist might argue that the agent themself is but a link in the chains of those mechanisms. For the agent to be free, they must be able to set those operations into motion, which means they must have the capacity to intervene in the natural causal order. However, humans seem to simply be part of this order. If every human action is caused by a reason which was caused by another reason, and so on, as Ayer (1982) argues, then it seems impossible that one has free will. On the other hand, if humans do not have underlying reasons for their actions, then it is merely chance that one chooses to act as one does. And if so, it is irrational to hold one morally responsible for that random choice - which is a conclusion we are not inclined to accept. It seems, then, that either way, the causal series of events simply “runs through” the agent, instead of beginning with the agent. This leads to the idea that humans do not really have alternatives that are truly open to them, and cannot really act in ways outside what they were always going to do, even if they think that they do. So free will and determinism seem to be incompatible.

Yet, perhaps we have defined free will wrongly - the ideal of free will may not be the capacity to do any and everything. A free choice does not have to exist outside the chains of causation. Ayer (1982) argues that the fact that one’s action is causally determined does not necessarily mean that one is forced to do it. He uses the example that when he gets up and walks across the room, we consider him free to do so. In contrast, when a pistol is pointed at his head to get him to walk across the room, he is forcibly constrained in a way that makes us consider this not a freely made decision. But when he made his decision without the pistol pointed at his head to get up, that choice was still equally an effect of the chains of necessity, as it could be causally explained in terms of his history and environment. So it seems that determinism is not antithetical to free will - it is not the action having a cause that makes it not a free action, but it having a certain type of cause that causes us to consider it not to be free.

Extending this argument, I believe that the definition of free will needs to be refined to be relevant in the way that it matters to us. I argue that the pure ability to do what one wants to without being constrained is not what we hope for when we think of free will. For instance, if I were to jump, I cannot stay suspended in the air no matter how much I want to. But the constraints of gravity do not make me feel that I do not have free will. If the incompatibilist wants to argue that only the absolute absence of any conceivable constraints will satisfy the definition of free will, that would seem to approach randomness or “chance”, as Hume (1748) puts it, which would then also absolve us of any form of moral responsibility - which is undesirable. Instead, I argue that free will is less about completely lacking restraints to do anything, but rather about being able to make choices given a certain set of circumstances that are limited but to an acceptable extent (eg. natural laws are acceptable limits, but human intervention is not.)

In this sense, free will and determinism may still be compatible in that predetermined set of options is available which we have the free will to select from. So long as that set of options, restricted by natural laws and other acceptable causes, is not constrained by other types of causes like human intervention, our standard for free will is achieved. For example, one may be born with a biological predisposition for dancing, but the exact style of dance - contemporary, modern, etc. - is entirely one’s preference. Furthermore, we are unable to predict what one will do exactly even if we may know everything about their history and environment (eg. even our closest family members can make decisions that surprise us). This suggests that free will exists within the realm of determined possibilities.

To this end, an incompatibilist would refute that the preference of the dancer would come down to predetermined causes (eg. one’s exposure to the dance style, or what one hears others say about that dance style, etc.). The causes that led to the dancer choosing a particular style originated from outside the agency or will of the dancer and led to internal effects within them, which then formed the dancer’s urge to take this particular “free” choice, which was in fact the only possible choice. Even if one argues that one can make a totally random decision, the incompatibilist would reply that it was not random, there was simply an underlying cause that we do not know enough about yet. Hence the inability for us to predict what people will do exactly is not proof that deterministic chains can be manipulated at certain points by free will, but may simply come down to insufficient knowledge about their history and circumstances.

Moreover, the incompatibilist might argue that even if we feel free to make a decision that is not random to us, such “free will” is in fact an illusion due to the presence of unseen causes. These causes restrict our set of options in a way that, if we knew about them, would make us think that we do not in fact have free will. For instance, if a person nearly drowned when he was a young child, and later repressed that memory so that he felt a strong aversion to large bodies of water without knowing why, we would not consider that person’s decision to avoid going near the ocean a choice made freely, even if he seems to feel it quite a natural and free decision for himself. Arguably our minds, subconsciously or not, are impressed by many experiences outside of our control, from childhood till now, that continue to shape our preferences, which then determine our behaviour. While we may think these preferences are our free choices, in fact we are simply adhering to these mental impressions stamped onto us. Thus the incompatibilist might conclude that free will has no place in determinism.

While it may be true that causes originating from outside oneself seem to render it impossible for one to take any other option than what one does, I would argue that even then, one is free to make the choice that one wants to (even if one cannot make the potential alternative choice that one does not intend to). Frankfurt (1969) offers examples which separate the issue of free will from that of moral responsibility, but I shall use his examples specifically to argue that free will can exist in spite of the restriction of other possibilities. Frankfurt gives the example of a man, Jones, who decides that he will do something, and is then threatened with a penalty if he does not do that thing. If he is the kind of person who would continue to act on the basis of his original intention anyway, we consider that he is morally responsible for that act, which I believe suggests that he is actually free to act in the way that he intends (even if he is not free to act otherwise). This example proves that even if one does not have the freedom to act in the way one does not intend to, one does have free will to act in the way one intends to, which is what matters. This may seem trivial, but in this way free will and determinism can indeed coexist; alternate paths may really be closed off from us but we only want to walk down the one path open to us anyway. Going back to the idea of a natural causal order which seems to run through an agent, I think the agent can still be freely playing out their role in the causal order, even if it were not possible for them to choose not to do so. Hence, determinism and free will can still be compatible.

To conclude, free will and determinism can be compatible, as firstly, free will requires determinism, secondly, whether we consider that something has been done freely or not relies on how it was caused instead of whether it was caused at all, and thirdly, an agent might freely play within a sandbox of possibilities restricted by determinism. Lastly, even if one is not free to make the decisions that one does not intend to, one is free in making the decisions that one does, leading us back to a compatibilist view.


Hume, D., & Millican, P. (2007). An enquiry concerning human understanding (Oxford world's classics (Oxford University Press)). Oxford ; New York: Oxford University Press.

Ayer, A. J. (1983). Freedom and Necessity. In Free Will. Oxford University Press.

Frankfurt, H. G. (1969). Alternate Possibilities and Moral Responsibility. The Journal of Philosophy, 66(23), 829–839.