1. Introduction
In this article I’ll provide strong experimental evidence for free will, where by “free will” I mean having the ability to control one’s actions (this is a pretty standard definition of “free will” in philosophy). I’ll also respond to some bad “scientific” objections to free will (really philosophical objections under the guise of science) in addition to a couple other bad objections to free will.
2. Experimental Evidence for Free Will
2.1 The Experiment
Recall that the working definition of free will is having at least some control over our actions, that at least some of our actions are up to us. We can do a simple experiment to see if we can control our actions: try to move our hand and see whether it moves in the way we tried to make it move. If we try to move our hand and we observe that it moves in the way we tried to make it move, we have evidence of being able to control our actions to at least some degree. I think this simple arm moving experiment provides very strong evidence, but let’s approach this analytically. The reasoning for this arm-moving experiment providing evidence for free will goes something like this:
| (1) | I try to move my arm in a certain way. |
| (2) | My arm subsequently moves in that certain way. |
| (3) | Conclusion: I have at least some control over my actions (in other words, I have free will on the aforementioned definition). |
This is an inductive argument, which roughly means that the premises are intended to make the conclusion likely even though it’s logically possible to have true premises and a false conclusion. For example, one could say that the fact that my arm moves in the way I tried to make it move is simply a coincidence. It may not be a very likely possibility, but it is still technically possible and so it’s still technically possible to have true premises and a false conclusion here. That said I think this is a strong inductive argument (in logic an inductive argument being strong means that the premises if true would make the conclusion highly probable).1
So what could be said in response to this argument? If the inductive argument is too strong one can go after the premises. One could deny premise (2), say that the fact that my arm seems to move in the observed fashion is invariably an illusion or hallucination no matter how many times I repeat this experiment. I suspect that even most free will deniers won’t go for such a highly implausible belief. That leaves premise (1). I suppose one could say that the fact that I’m trying to move my arm is an illusion, but that’s a very extraordinary claim that requires very strong evidence. So I don’t find the denial of premise (1) much more plausible than the denial of premise (2), at least not without some very strong evidence for it.
In logic, an inductive argument that is both strong and has all true premises is called a cogent argument. I think the above (1)-(3) argument is cogent; the argument is inductively strong and we have excellent reason to believe that the premises are true. The simple arm-moving experiment seems to provide powerful evidence for free will as I have defined it.
2.2. Determinism
So far I haven’t said much about determinism, the view that only one outcome is possible given sufficiently specified initial conditions. Some people believe that free will is compatible with determinism, and this view is called compatibilism, whereas incompatibilism holds that free will is not compatible with determinism. Libertarians accept both incompatibilism and the view that we have free will, thinking that we can choose among genuine alternatives given the same initial conditions. I haven’t taken a side about whether compatibilism or libertarianism is true here (nor does the (1)-(3) argument take sides about whether compatibilism or libertarianism is true), but both compatibilists and libertarians can accept the (1)-(3) argument above. By my lights, the fact that we have free will is a lot easier to establish than either libertarianism or compatibilism.
Note that although the (1)-(3) argument is agnostic about whether incompatibilism is true, if we did believe that incompatibilism is true and also believed that the (1)-(3) argument is cogent, we would be rationally compelled to accept libertarianism as probably true.
3. Bad Objections to Free Will
3.1 Why Objections Matter
By my lights reasonably denying the existence of free will would require very strong evidence against free will to counter the very strong evidence for free will (e.g., from the arm moving experiment). But sometimes extremely weak evidence is given instead, and sometimes bad arguments against free will are put under the label of “science” when in fact they’re really just bad philosophical arguments, and those are what I’ll discuss next.
3.2 Bad “Scientific” Objections to Free Will
3.2.1 Overview
I put “scientific” in quotes because the alleged scientific objections are really philosophical arguments cloaked in false scientific authority. First I’ll start with an argument from determinism, then an argument from physicalism (the view that the physical world is all there is).
3.2.2 Argument from Determinism
In the realm of physics, determinism is either frequently true or close enough to it for all practical purposes (there is arguably indeterminism at the quantum scale). For simplicity I’ll refer to “determinism” as the view that at the macro-level as well as inside the brain are all at least de facto deterministic, and indeterminism as the denial of this deterministic view.
At any rate, one “scientific” objection is this: determinism is incompatible with free will, yet our brain is the source of behavior and decision making. The question then becomes whether our brains are completely deterministic as opposed to there being some meaningful role for indeterministic free will. Determinism applies in all sorts of places where we’ve scientifically tested it including the brain in at least some cases. So, by extrapolation, it probably applies completely inside the brain and thus any observations to the contrary are illusory. Consequently, we do not have free will.
First off, the assumption that determinism is incompatible with free will is controversial, but let’s assume it’s true for sake of argument, so that any observation of us controlling our actions would imply that indeterminism is true. While this “scientific” argument for determinism holding true everywhere may look impressive at first, consider how it looks when we approach it analytically:
| (4) | Most observed phenomena inside and outside the brain is deterministic. |
| (5) | Conclusion: any observations that imply the existence of indeterministic phenomena inside our brains are illusory. |
This is a bad argument, and to illustrate why, consider the following scenario. A husband and wife are visiting a zoo in the town they live in. The husband says, “I’ve seen nearly every bit of this town, and in most observed cases inside and outside the zoo, we have not observed any zebras. Therefore, our town has no zebras.” His wife says, “What about those things that look like zebras in that enclosure?” He replies, “That’s an illusion, and we know it’s an illusion because in all other observations inside and outside the zoo we don’t see zebras.” This is obviously terrible reasoning. The fact that there are no zebras outside a certain zoo enclosure is insufficient grounds for believing that the observations implying that zebras are inside the enclosure are illusory. Similarly, the fact that there is no indeterminism in most observed cases would be insufficient grounds to believe that observations implying that indeterminism sometimes occurs in the brain are illusory. If we knew that determinism is incompatible with free will, then the simple arm moving experiment would seem to show that indeterminism is true with respect to us, and the bad (4)-(5) argument isn’t nearly enough to conclude that, for example, the observation of us trying to move our arm is an illusion.
3.2.3 Argument from Physicalism
Another argument is that free will is inconsistent with physicalism, i.e., if all that exists is the physical world with its physical laws as physicalism claims, then free will cannot exist. Science is the best tool we have for studying reality, and the physical world with its physical laws are the only things that exist within the realm of science. The existence of free will is thus contrary to science.
There are multiple problems with the above argument, one being that whether physicalism is incompatible with free will is controversial (this is related to the point of whether free will is compatible with determinism), but for sake of argument let’s assume free will is incompatible with physicalism. Another issue is that “physicalism” is not a scientific position: it is a philosophical one. One might think science is the best (or only) tool we have for acquiring knowledge, but even that is a philosophical position (one that is called scientism) rather than a scientific one (and a controversial philosophical position at that; one could argue that we know e.g., truths of formal logic better than we know truths of science).
In response, one could concede that physicalism is a philosophical position but also claim that science supports it. How does science show that physicalism is true though? Science may inform us that the physical world and physical laws exist, but it’s a big leap to go from that to the view that only the physical world and physical laws exist. Moreover, premises (1) and (2) seem like scientific observations; the fact that I try to move my arm is a psychological fact, and the subsequent arm movements also fall into the realm of science (biology, physics, etc.). Given the strong experimental evidence for free will, if free will is inconsistent with physicalism, then so much the worse for physicalism.
Against this, one might respond by saying we have better reason to believe that physicalism is true than we do to accept free will. But (a) that seem dubious given the strong experimental evidence for free will; and (b) whether physicalism is true can’t be justified by uttering the word “science.” One would need a real argument.
3.3 Other Bad Objections
One bad objection involves observed instances of us having no free will (perhaps due to mental illness, perhaps due to external and mechanically introduced brain stimulations) and from there argue that we have no free will. But notice that this is a bad argument:
| (6) | There are some instances in which we do not have free will. |
| (7) | Conclusion: we never have free will. |
This is obviously a hasty generalization particularly given the strong experimental evidence for free will as explained in the (1)-(3) argument. After all, the fact that we at least sometimes have control over our actions does not imply that we always have control over our actions.
A more promising (but still bad) argument goes like this: in reality there is only determinism and randomness. Free will is incompatible with determinism, and randomness can’t do the job either (imagine rolling dice; the dice didn’t “choose” the outcome, it was just blind, mindless chance). Therefore, free will doesn’t exist.
One problem of course is that whether free will is incompatible with determinism is controversial, but let’s once again assume that it is for sake of argument. If by “randomness” we mean indeterminism with no mind selecting the outcome, then yes randomness isn’t really free will. But then “determinism or randomness” is a false dichotomy; there is a third alternative: indeterminism with a mind selecting the outcome. This third alternative is what libertarians accept. One might think this libertarian belief is false, but the point is that one would have to do more than present a “determinism or randomness” false dichotomy fallacy. One would have to present a real argument against libertarianism, and there isn’t anything logically incoherent (at least not obviously so) about a mind choosing from among multiple possible options in the sense that libertarianism affirms. If one says that we never observe a mind doing that, one could (if we’re all assuming incompatibilism) point to the experimental evidence that we do in fact observe minds doing that when, for example, we observe that our arm moves in the way we tried to make it move. The (1)-(3) inductive argument seems quite formidable.
4. Conclusion
The observation of one trying to move their arm and that the arm subsequently moves in the way they tried to make it move provides strong evidence for free will (having the ability to control one’s actions to at least some degree). Put more analytically in the form of an inductive argument:
| (1) | I try to move my arm in a certain way. |
| (2) | My arm subsequently moves in that certain way. |
| (3) | Conclusion: I have at least some control over my actions (in other words, I have free will). |
The above argument is agnostic about whether libertarianism or compatibilism is true, and both libertarians and compatibilists can accept the argument as cogent. To oversimplify a bit, there are two ways the argument can fail: (a) true premises and a false conclusion; or (b) a false premise.
| (a) | True premises, false conclusion. One could say that the fact that my arm moves in the way I tried to make it move is simply a coincidence, and continues to be a coincidence no matter how many times I repeat the experiment (and many others like it!), but this seems unlikely. The argument is inductively strong; i.e., the premises if true would make the conclusion (one having at least some control over their actions) highly probable.2 | ||||
| (b) | A false premise. At least one premise is false. Going backwards a bit:
|
Those who deny free will are in the awkward position of dismissing inconvenient evidence as illusory, but to do that rationally you’re going to need more than bad arguments. Examples of bad “scientific” arguments:
- Argument from determinism: Determinism applies in all sorts of places where we’ve scientifically tested it including the brain in at least some cases. So, by extrapolation, it probably applies completely inside the brain and thus any observations to the contrary are illusory.
- Objection: The above argument is a terrible reason to dismiss contrary evidence as illusory; it’s analogous to a man observing there are no zebras outside a certain zoo enclosure and concluding that therefore the observation of zebras inside that enclosure is illusory. If we assume for sake of argument that determinism is incompatible with free will (a controversial philosophical position), the observations in the arm moving experiment provide strong evidence for determinism being false.
- Argument from physicalism: Free will is inconsistent with physicalism. Science is the best tool we have for studying reality, and the physical world with its physical laws are the only things that exist within the realm of science. So we have a scientific objection to free will.
- Objection: Physicalism is a philosophical position, not a scientific one. Science may confirm the existence of the physical world with physical laws, but it’s a big leap to go from that to the view that only the physical world with its physical laws exist.
- Objection: Suppose arguendo that free will is incompatible with physicalism (a controversial philosophical position that would need to be argued for!). We have scientific observations via the arm moving experiment (e.g., the fact that one tried to move their arm would be a fact of psychology) showing that free will exists, so if free will is incompatible with physicalism, so much the worse for physicalism.
- There is experimental evidence for free will. Remember that free will is the ability to control one’s actions. The arm moving experiment provides mundane but surprisingly strong evidence for free will as explicated in the (1)-(3) argument. Some people arguing against free will completely ignore the evidence for free will.
- Think logically and analytically. Breaking down arguments into clearly stated premises and conclusions helps analyze the argument’s reasoning. When we do this, we see how strong the experimental evidence for free will is (e.g., denying the fact that I tried to move my arm is a very extraordinary claim) and such analysis also helps us see how weak some arguments against free will are, like the (4)-(5) argument from determinism.
- Beware “scientific” objections to free will. That is, beware someone calling their philosophical objections “science.” Some of these “scientific” arguments against free will are actually just bad philosophical arguments that fail under scrutiny. Examples include the argument from determinism and the argument from physicalism as described in this article.
1 Note that if we define “control” as “exercising influence over,” to say that the inductive argument is strong is basically tantamount to saying that the fact that our arm moved in the way we tried to make it move is evidence for us having been able to exercise influence over moving that arm. That fact that this inductive argument is strong is thus almost a tautology. ↩
2 See note 1 about defining “control” and its implications for inductive strength. ↩
