Arguments for Free Will

Years ago I wrote a post on my previous blog where I briefly outlined some arguments, off the top of my head, for free will. More recently I was approached by Christian Vision, an organization based in the UK, and asked if I could clean up the article and allow them to showcase it in English on their website, and put up a translation of it into Arabic as well. I decided to leave the previous (and relatively poorly written article) as it is, and to, here, provide a revamped version of the article which I will allow Christian Vision to use with proper acknowledgement of the source. Enjoy.


In this article I want to run through some of the arguments for libertarian free will which I feel provide a powerful cumulative case for belief in free will. The usual alternative to belief in free will is belief in determinism, and as such my arguments will be addressed to determinists. I wish, nevertheless, to acknowledge at the outset that there are some other positions one might adopt, such as so-called ‘soft-determinism’ or complete indeterminism; my arguments, though directed at determinists, should be palatable to anyone of any philosophical perspective. It is worth observing that in suggesting that free will is a genuine alternative to either determinism or indeterminism many are inclined to see a contradiction. The terms ‘determinism’ and ‘indeterminism’ are antonyms, logically excluding one another, and what one affirms the other negates. In such cases the predicates are generally thought to be disjunctively exhaustive; either something is determined, or it is not-determined. However, our grammar betrays us here. What we usually mean by ‘determinism’ (and what I will mean in what follows) is that every event is pre-determined. What we mean by indeterminism is that no event is determined. What we will mean by suggesting that freedom is an alternative to these doctrines is that a free act is determined by the individual, without being pre-determined.

What I mean by libertarian free will, often also called ‘categorical’ free will, is the notion that our actions, insofar as they are free at all, are not merely the consequences of their causal antecedents. Note that I use the very broad term ‘causal antecedents’ in order to anticipate even bizarre forms of determinism (for instance, versions of determinism which might appeal to future events causing past ones, so that causal and temporal antecedence don’t go hand-in-hand). However, in addition to a free action not following deterministically from (temporally, or logically) prior causes, we must also say that a free action must be volitional, intentional, and that it arises from the individual who is free. It would do no good to argue that determinism is false, and then end up with merely random indeterministic events (none of which can be free for the same reason causally pre-determined ones cannot be free). What we want is a decision determined by individuals, without being pre-determined by anything either within or outside of the individuals. A rough, somewhat technical definition would look something like this:

S is libertarian free =df  S has at least one choice between at least two options A and B, where no causal antecedents to S’s choice determine that S chooses either A or B, and S’s choosing of A or B is an intentional act of causally determinative volition on the part of S.

So, if a person is free in this sense then we can imagine that, if they in fact chose A given options A and B, there is a logically possible world in which that person chooses B instead, even given the exact same set of causal antecedents (whether temporally prior or not). Here we must simply be careful to understand ‘choose’ as an action of the will. We need not commit ourselves to the view that a libertarian free agent could literally have acted any differently than she did, but only that her action wasn’t causally coerced. This caveat is intended to evade the problems posed by ‘Frankfurt style counter-examples.’ Briefly, a Frankfurt style counter-example runs something like this:

“An agent S is in the process of deciding which of n alternative acts A…,Ak…,An to perform. He believes (correctly) that he cannot avoid performing some one of these acts. He decides to perform, and, acting on this decision, does perform Ak. But, unknown to him, there were various factors that would have prevented him from performing (and perhaps even from deciding to perform) any of A…,An except Ak. These factors would have “come into play” if he had shown any tendency towards performing (perhaps even towards deciding to perform) any of A…, An except Ak. But since he in fact showed no such tendency, these factors remained mere unactualized dispositions of the objects constituting his environment: they played no role whatever in his deciding to perform or in his performing Ak.”[1]

At minimum we need to maintain that an agent S’s choosing Ak is not causally coerced, though I think there is room to argue that S should have been able, at least initially, to will otherwise.

In this article I will not spend much time arguing for the coherence of libertarian free will (since plenty of excellent philosophers have already done this work, and because it would detract from my purpose here to distract myself with such a task). I will simply presume it’s coherence, and offer arguments for its truth.

What reasons have we for believing in the categorical freedom of the will? Well, first and foremost we can observe that it enjoys a strong prima facie plausibility – at face value, it seems to accord with our experiences of ourselves. Children believe in free will. They may not be able to articulate that belief with any philosophical sophistication, but, then again, most adults who don’t study philosophy can’t articulate any of their beliefs with philosophical sophistication. People in general naturally believe in free will, at least until they are persuaded to believe otherwise. An old philosophy professor of mine once joked that if you wake a determinist suddenly from his sleep he finds himself believing in free will, at least until he comes back to his ‘philosophical’ senses. The joke is anecdotal (of course), but it highlights the point that if there is such a thing as a ‘default’ position in this matter, it would be the belief in free will, and not determinism.

Determinists are, nevertheless, often under the impression that determinism is the default position, and so they forget to offer any arguments for its truth. Indeed, arguments for determinism are rare, and none of them are, all things considered, very persuasive. Somebody may think, for instance, that determinism would follow from the theses that (i) materialism (in particular about human beings) is true, and (ii) that physics operates deterministically. However, the second thesis is seriously undermined by advances in quantum mechanics which suggest to many that, at least at the quantum level, physical events occur indeterministically. The first thesis is in even worse shape, for, no matter how earnestly one may search, there is a deafening absence of any arguments for materialism in the philosophical literature. What is worse, materialism about the human mind is today considered the Achilles’ heel of materialism itself. Back in the 1960’s materialists (like J.J.C. Smart and Herbert Feigl) were optimistic about reducing the mind to the brain, but all attempts to work out this reduction failed miserably and quickly. As one materialist philosopher laments:

“For many of us who, like me, went to graduate school in the late 1950s and early 1960s, Smart’s and Feigl’s materialism was our first encounter with the mind-body problem as a systematic philosophical problem. Their approach sounded refreshingly bold and tough-minded, and seemed in tune with the optimistic scientific temper of the times. It was an intriguing and exciting idea that mental events could just be brain processes, and that scientific research could show this, just as science showed us that light was electromagnetic radiation, and that genes were DNA molecules. But the identity theory was unexpectedly short lived – its precipitous fall began only several years after its introduction.”[2]

Reductive materialism about the mind fell still-born from the academic presses, and even today the mind and mental properties (such as intentionality, and ‘qualia,’ which seem immune to materialistic reduction) pose the greatest problem for materialism in general, not to mention materialism about human beings in particular. What other arguments are there for determinism? Not many. What arguments are there for free will? Many.

To begin with, belief in free will seems epistemically justified. I already noted that it enjoys a prima facie plausibility, but now I want to go further and suggest that belief in free will is an example of what philosophers call a properly basic belief. The notion of proper basicality employed here comes from reformed epistemology, according to which a properly basic belief is a belief which we are rationally justified in maintaining even in the absence of what would normally qualify as ‘evidence,’ and which we would be irrational to reject in the absence of some overwhelmingly good reason to think we were wrong about it. Commonly used examples are belief in the external world (i.e., that we aren’t ‘in the matrix’ or just dreaming), or belief in other people’s minds (i.e., that solipsism is false). My favorite example is the belief in the reality of the past – there is no way to prove, or even provide evidence for, the belief that the past is real as opposed to the belief that the world popped into existence moments ago with the appearance of age (eg. with fossils in the ground from creatures which never lived, or food in your stomach from a meal you never ate, or even memories in your head from things you never did). There is no way to prove any of these beliefs by appealing to evidence, for no evidence counts in favor of these beliefs and counts against their alternatives. It is because of beliefs like this that many philosophers appeal to the notion of proper basicality.

A properly basic belief, then, is one which we are rationally justified in maintaining without having any demonstrative arguments for it, and which we would be irrational to abandon unless and until presented with some overwhelmingly strong argument(s). Properly basic beliefs are usually ones which we naturally come to believe, and which enjoy a strong prima facie plausibility; but belief in free will is exactly like that, and therefore seems to be a properly basic belief. Therefore, in the absence of any overwhelmingly good reason(s) to doubt that we have free will, we seem to be rationally justified in maintaining our belief in free will even in the absence of any additional arguments.

I anticipate one obvious objection to this, which is that this ‘reformed epistemology’ is just one option among many different theories of epistemology (i.e., theories of how we can know anything, where ‘knowing’ means something like having a true and justified belief). However, whatever epistemology one appeals to, there are certain beliefs which are so basic, so universal, so intuitive, and so natural to us (like the belief in the reality of the past), that if one’s epistemology doesn’t allow us to rationally maintain those beliefs we may as well take that to be a reductio ad absurdam of that epistemological system. However, as I have argued, belief in free will is one of these kinds of beliefs. Therefore, any epistemology that won’t allow, in principle, for belief in free will to be justified ought, by reason of that (if nothing else) to be abandoned.

If one accepts reformed epistemology, then this first argument alone should be enough to rationally satisfy anyone’s need for a persuasive argument for free will. If one merely adopts an epistemology which allows free will to be satisfied, but rejects (or at least does not as of yet accept) this notion of ‘properly basic’ beliefs, then one remains open to more arguments. In what follows, then, I will provide a number of other arguments.

Another epistemological argument attempts to show that we must have free will. Consider a textbook case of an epistemically unjustified belief, such as believing in God simply because you flipped a coin and it happened to land ‘heads’ instead of ‘tails’ (where you previously determined that if it landed heads, you would believe in God, and if not, then you wouldn’t). Your belief could be correct, but even if it were it wouldn’t be justified. Why isn’t it justified? Because the method you used for your belief-formation doesn’t aim reliably towards the truth. To have a ‘justified’ belief means, at least in part, having formed a belief in such a way that the belief-forming processes in principle aim reliably toward the truth. However, suppose (for reductio) that determinism is true. This means that everything each of us believes is entirely the product of deterministic processes. Whether we believe in God or not, whether we believe in the deliverances of science or not, and even whether we believe in determinism or not, is all a matter of strict determination. This means that our belief-forming processes all operate deterministically, but it also means (given the obvious and wide variety of human beliefs) that this process does not reliably aim towards the truth. Thus, if determinism is true, then our belief-forming processes do not reliably aim towards the truth, and we have good reason to doubt all of our beliefs (including our belief in determinism). In other words, if determinism is true, then none of our beliefs can be trusted, none of them can be rationally justified, including our belief in determinism, which ultimately makes determinism, as a philosophical hypothesis, appear self-defeating. Notice that the same argument can be run against indeterminism, so that strict determinism, or random indeterminism, will lead either way to the same philosophical rut. It is only, in principle, if our belief-forming processes involve some measure of freedom of the will, that we can begin to speak meaningfully about epistemic justification (note that freedom here doesn’t make justification inevitable, but it does make it possible, and that’s the point).

A more radical point can be made about determinism’s implications not only for epistemic justification, but for rational thought itself (and the same point can be made, by way of parody, for indeterminism). Consider the following words from H.B.W. Joseph, from his compiled lectures at Oxford published under the title Some Problems in Ethics (for ease of mind we can imagine the following to be addressed to somebody who holds a familiar form of determinism – namely, scientific and physicalistic determinism – but the general point can be made to apply to any form of determinism with little amendment);

“If thought is laryngeal motion, how should any one think more truly than the wind blows? All movements of bodies are equally necessary, but they cannot be discriminated as true and false. It seems as nonsensical to call a movement true as a flavour purple or a sound avaricious. But what is obvious when thought is said to be a certain bodily movement seems equally to follow from its being the effect of one. Thought called knowledge and thought called error are both necessary results of states of brain. These states are necessary results of other bodily states. All the bodily states are equally real, and so are the different thoughts; but by what right can I hold that my thought is knowledge of what is real in bodies? For to hold so is but another thought, an effect of real bodily movements like the rest…. These arguments, however, of mine, if the principles of scientific [naturalism] … are to stand unchallenged, are themselves no more than happenings in a mind, results of bodily movements; that you or I think them sound, or think them unsound, is but another such happening; that we think them no more than another such happening is itself but yet another such. And it may be said of any ground on which we may attempt to stand as true, Labitur et labetur in omne volubilis aevum. [It flows and will flow swirling on forever].”[3]

Thus, if all our thinking is the result of a deterministic process then we have no ultimate control over our thoughts, any more than we do over our actions (a point to which we shall return below when examining the moral argument). Our beliefs cannot be the product of rationalization, and to that extent cannot be genuinely ‘rational,’ where that word implies the ability, in principle, of the human mind to move itself in such a way as to recognize the truth. There is no such ‘ability’ at all on determinism, for even if the mind happened to reflect the right stuff in the right order, it wouldn’t be doing so by any internal principle, but merely by accident. The laws governing the activity of the mind on this view are not ‘rational,’ but physical, and ultimately indifferent to truth. How great and ridiculous a charade it is when a determinist pretends to participate in a rational exchange of arguments in order to persuade an interlocutor – for, on their view, those who believe in free will are determined to believe in free will, just as the determinists are themselves determined to be determinists. This thought itself, should it occur to them, is also determined. There is absolutely no way for a determinist to make room in their account either for the rational selection of beliefs, or even for the rational content of beliefs themselves (since beliefs, on this view, are merely brain-states, and mere brain-states, as such, cannot be about anything, anymore than any physical object, as such, can be about anything). Thought is controlled by physical processes ultimately indifferent to the truth, and beliefs are merely physical states of the brain, and as such can neither be true nor false.

I am not alone in making this observation. It is, in fact, well documented in the philosophical literature. Robert P. George (who lectures at Princeton on the philosophy of law, and related areas) puts it nicely;

“Christian philosophers such as Germain Grisez, Joseph M. Boyle, Jr., and Olaf Tollefsen have rigorously shown, however, that the denial of free choice is rationally untenable, because it is a self-referentially contradictory claim, a self-defeating proposition. No one can rationally deny free choice, or claim as illusory our ordinary experience of freely choosing, without presupposing the possibility of free choice. To deny free choice is to claim that it is more rational to believe that there is no free choice than to believe that there is. But this, in turn, presupposes that one can identify norms of rationality and freely choose to conform one’s beliefs to those norms. It presupposes that we are free to affirm the truth or falsity of a proposition, our desires or emotions or preferences to the contrary notwithstanding. Otherwise, the assertion of no free choice is pointless. The person who says people can’t freely choose presupposes that there are reasons for accepting his claim, otherwise his act of asserting it would be pointless. But our ability to understand and act upon such reasons is incompatible with the idea that one is caused by his desires or by outside forces to accept or not accept such claims. So someone who denies free choice implicitly contradicts his own claim.”[4]

Another argument comes from our moral experience. In our everyday life we encounter certain moral predicaments, and we accept moral realities as readily and firmly as we accept physical realities. In fact, belief that the world involves a certain moral structure, and that some things are really good, whereas other things are really evil (as opposed to being simply pleasurable or displeasurable as a matter of taste) is also a properly basic belief. It is a belief which we form naturally, and in which we have no good reason to doubt. One Christian philosopher named William Lane Craig has gone so far as to note that any argument one might give against moral realism can be parodied into an almost identical argument against belief in the physical/external world. His point is that we have no more reason to doubt one than we have to doubt the other, and his observation seems to me to be a very perceptive one. If he is right, then we have good reason to be moral realists. However, moral responsibility makes sense only with the assumption of freedom. As Peter van Inwagen puts it;

“But why should anyone care whether we have free will or whether determinism is true? [the answer is that:] we care about free will because we care about moral responsibility, and we are persuaded that we cannot make ascriptions of moral responsibility to agents who lack free will.”[5]

One is morally blameworthy for a wrong act only if they were not causally compelled to commit the act. Otherwise, to blame a person for their actions is as senseless as blaming a mountain for having an avalanche at the wrong time. Even if somebody were to insist that a serial killer is morally culpable because their actions weren’t unintended (i.e., they acted in accord with their desires, and so intended to kill people, which is quite different from the case of a person who accidentally kills somebody), still, on determinism, the problem is that the serial killer couldn’t help but want to kill people. Perhaps the determinist will argue that the killer didn’t even want to not want to kill people, but this is also out of the killer’s control. On this view, nothing is in the control of the individual in a way that will allow, in principle, for moral culpability. All this is to say that, on determinism, nobody is ever truly morally responsible for anything they do. Their acts may be good or evil in some abstract sense, but they are no more morally responsible for them than the ocean is responsible for tsunamis.

Does such a view comport well with our moral experiences? No, it doesn’t. It doesn’t do justice to our feelings of guilt, or our feelings of admiration for the morally upright. If we ever do anything for which we are morally responsible, then we must have free will. However, we do do some things for which we are morally responsible. Therefore, we must have free will. The cost of denying the conclusion is to deny one or both of the premises, but they both seem as solid and immovable to the mind as almost any other belief which we would, under ordinary conditions, never give up. In fact, belief in moral responsibility also qualifies as a properly basic belief, so that those who accept the plausibility of reformed epistemology will have gained an additional reason for affirming the freedom of the will.

A similar point can be made concerning the philosophy and nature of law. In law, there are distinctions between intentional killing (i.e., murder), and unintentional killing, and even in cases of intentional killing the law recognizes a difference between somebody who is insane intending to kill somebody, and somebody who is ostensibly sane intending to kill somebody. In both cases a ‘killing’ took place, and in both cases it was intentional (making the act murder), and yet the person who is insane does not receive as severe a legal penalty as the person who was sane. Why not? Because the presumption is that the person who was sane exercised a greater degree of freedom with respect to their actions than the person who was insane. The insane have less genuine freedom than the sane. Such a distinction, recognized implicitly by jurisprudence, also betrays the assumption of freedom in law. Free will is as much a basic assumption of law as the assumption that light travels at a constant rate between any two points is a basic assumption of relativity theory in physics. A law which punished the insane and the sane alike without distinction would plausibly be unjust, but the distinction only makes sense if people have free will to begin with (otherwise the distinction seems arbitrary and absurd, and therefore not an expression of justice). Just law, therefore, presupposes freedom of the will. This argument is ultimately a footnote to the previous argument, since the concept of legal justice is ultimately bound up with (and is in fact an extension of) the concept of moral justice, and so to deny moral realism will ultimately lead to nominalism about legal justice. However, often different arguments resonate with different people, and so I submit this argument for those who have a strong commitment to legal justice, even if they have confused intuitions about richer philosophical notions of morality.

Another argument for free will, or at least against determinism, comes from our modal intuitions. What philosophers mean by a modal intuition is a rational intuition about things which are possible, impossible, contingent, incontingent, actual and necessary. On determinism, everything is ultimately a necessary fact. However, we all have a strong rational intuition that there is a distinction between necessary facts, such as that 2+2=4, and contingent facts, such as that you are now reading this sentence. The former could not have failed to be true, whereas the latter could quite easily have failed to be true. Even scientific laws are stated as counter-factuals, about what would happen, ceteris paribus, under certain conditions – but such statements ultimately make no sense on determinism because they are conditional statements, and the antecedent of the conditional, if it fails to be true, makes the whole conditional statement ‘true’ in a meaningless sense. That antecedent of the conditional, if it fails to be true, is necessarily false according to the determinist, so that determinists have to rethink even how we generally conceive of scientific laws. Scientific statements presuppose modal commitments. Despite the strength with which such rational intuitions about modality come, however, determinism threatens to collapse all of our modal distinctions. This gives us tremendously good reason to doubt determinism. One is left with having to affirm either freedom of the will, or else indeterminism, and freedom of the will is at least more plausible than indeterminism. Moreover, indeterminism would propose that all facts are ultimately brute facts (i.e., non-necessary truths for which there are no explanations at all). Those who share, with me, a strong commitment to the intuition that every contingent fact must have some explanation in reality (even if we cannot or do not find it), will find it just as difficult to swallow the doctrine of indeterminism as they do the doctrine of pre-determinism. I will not here go through the arguments for thinking that free choices can be ‘explained’ even if they aren’t ‘entailed,’ but just note that, so far, the doctrine of free will holds the best hope of satisfying our modal intuitions.

There are other relatively obvious arguments which can be adduced for free will, such as arguments from authority. One can point out that the majority of the greatest thinkers in the history of the (at least western) world have believed in free will, or that the vast majority of mankind believes in free will. We can point to certain other authorities like the Catholic Church, or Jesus of Nazareth (or others, which we can select as we please). Ultimately arguments from authority rarely change anyone’s mind. Most people who would be moved by them, are already persuaded, and most people who aren’t persuaded already are not likely to be moved by them. Nevertheless, it is worth noting the existence of such arguments for at least two reasons: (i) some people, at least, really are moved by such arguments, and (ii) even when somebody isn’t moved by such arguments it helps them put their own view in perspective – when a person can see that they hold the view of a fringe minority they become implicitly more skeptical about it and desire to find good arguments for it. The determinist, however, is not likely to find any such arguments, which will help at least dislodge in her mind the delusion of determinism’s plausibility.

Finally, hearkening back to modal intuitions and free will, it seems that, upon deeper reflection, every argument for God’s existence can be taken as providing an additional implicit argument for libertarian free will. The thinking goes like this. First, the existence of the world is not a necessary fact, but a contingent one. Second, it is contingent, but not brute (unexplained). Take ‘the world’ here to signify what Copleston defined it as in his debate with Bertrand Russell: “the world is simply the real or imagined totality or aggregate of individual objects, none of which contain in themselves alone the reason of their existence.”[6] In this way we avoid inviting the confused response that there might be a multiverse ensemble that could explain our universe’s existence, since the multiverse itself will stand in need of an explanation, and it will, if it exists, be included in our concept of ‘the world’ as it is here used. If the world is both contingent and explained, then it seems it must be the product of free will. The only other options are to explain it deterministically, or to account for it indeterministically, but the latter is not an explanation at all, and the former threatens to collapse modal distinctions between the merely possible and the necessary. In fact, this argument could be run in reverse and made into an argument for God’s existence (even entailing that God must be a person, since only persons can exercise free will), though what we care about here is only arguments for free will. If our worldview includes a being like God (i.e., a maximally great transcendent creator), then God, at least, will need to have free will (on pain of either determinism or indeterminism – modal collapse, or brute facts). Thus, as soon as one admits that God exists, one can see another argument for free will on the philosophical horizon.

This list of arguments is by no means exhaustive. One could imagine an argument from miracles (eg. (i) if miracle M occurs then Christianity is true, (ii) if Christianity is true then we have free will, (iii) M occurs, (iv) therefore, we have free will), or even a Moorean-style argument (i.e., one where we suggest that we are more sure that we have free will than we can be that any argument to the contrary is sound), and I’m sure there are other arguments I haven’t considered. However, this collection of arguments seems to me to establish the overwhelming plausibility of the libertarian account of our actions, and seriously undermines the most popular alternative to libertarianism (i.e., determinism).


[1] Peter van Inwagen, “Ability and Responsibility,” In The Philosophical Review (1978): 202.

[2] Jaegwon Kim, Mind in a Physical World: An essay on the mind-body problem and mental causation, (MIT press, 2000), 2.

[3] Peter J. Kreeft and Ronald Keith Tacelli, Handbook of Catholic Apologetics: Reasoned Answers to Questions of Faith. (Ignatius Press, 2009): 72.

[4] George, Robert P. “A Clash of Orthodoxies.” First Things no. 95 (1999): 38.

[5] Peter van Inwagen, “Ability and Responsibility,” in The Philosophical Review (1978): 201.