Do humans have free will?

Some definitions

Determinism is the belief that everything that happens is determined by antecedent conditions together with the natural laws.

Free will is harder to define, but may be seen as the capacity of rational agents to choose a course of action from among various alternatives. (Of course this doesn’t deny that many of our choices may not be physically possible – e.g. flapping our arms and flying.)

The key concept of free will seems to be that that we could have chosen otherwise, and if the same physical situation arose again, we could make a different choice, but several things are probably required for this – that the choice is voluntary (i.e. isn’t imposed from outside), it is conscious and intentional, and that we are the originating agent of the action (i.e. the cause isn’t external). This “fully free” will is often called libertarian free will.

Compatibilism is the belief that determinism and free will are both compatible in humans (though the free will involved is often less than libertarian free will), while incompatibilism is the belief that they are not.

Naturalism is the belief that nature is all there is, and physicalism is the belief that everything is physical or can be reduced to the physical.

Dualism is the theory that the mental and the physical, or mind and brain, are, in some sense, radically different kinds of thing, and therefore that the physical sciences cannot fully explain the mind. The contrary view, that mind and brain are both physical, is monism, and is the logical conclusion from naturalism.

(All definitions taken from various pages of The Stanford Encyclopedia of Philosophy (SEP).)

Thus the main issues are (1) which of dualism and monism is true, and (2) whether naturalism allows free will. And the main arguments come from neuroscience and philosophy.

Neuroscience

I have been able to find a few scientific studies that address the question of free will and dualism:

Wilder Penfield

More than half a century ago neurosurgeon Wilder Penfield, in the course of performing surgery for patients suffering from epilepsy, mapped brain functions in more than a thousand patients using electrical stimulation. He found that patients were able to distinguish between mental events they had willed themselves, and those produced by stimulation, suggesting to him that higher mental functions such as consciousness, will, imagination and reasoning were not produced by the brain but by a non-physical mind that interacts with the brain.

However more recent experiments conducted by Ammon and Gandevia found that it was possible to influence which hand people move by stimulating parts of the brain without them being aware of it, which may contradict Penfield’s conclusions.

Benjamin Libet

About 30 years ago, neurologist Benjamin Libet peformed a number of experiments where people were asked to choose a random time to move their finger. By obtaining feedback from them, plus measuring brain activity, Libet found that the unconscious brain activity that led to the action occurred before the conscious intention to move reported by the subject.

Other neuroscientists were able to replicate the experiments and conclude that the initiation of actions is unconscious. This suggests our conscious will does not cause us to act – meaning we don’t have free will. However many scientists believe the experiments should be interpreted as not disproving free will.

It may be that Libet’s experiments can be used to support dualism – i.e. the conscious intention to move the hand occurs in the non-material mind, and is not measured by probing the physical brain.

Mario Beauregard

In his book Brain Wars, research neuroscientist Mario Beauregard outlines a range of scientific studies that suggest to him that the mind is more than the physical brain:

• The placebo effect: the mind’s beliefs have the power to cure, or prevent cure.
• Neurofeedback: the mind can exert conscious control over physical brain activity.
• Neuroplasticity: controlling the mind with practices like meditation can change the structure of our brains.
• The psychosomatic network: a positive attitude can improve health and even switch genes on and off.
• Near death experiences and psi phenomena: the mind/brain does amazing things that we wouldn’t think possible.

Many of these claims are controversial, and many may have alternative, naturalistic, explanations, but Beuregard claims that a rising number of colleagues believe these results show that physicalism is wrong, and the mind exercises control over the brain – and presumably allows free will. His view is thus somewhat similar to dualism.

The general conclusion of neuroscientists

Most neuroscientists are naturalists and reject dualism because it cannot be proved, or even investigated, scientifically. Most I have read don’t discuss the philosophical aspects all that much, but the way they describe the brain’s processes suggests to me that they don’t think we have free will as we have defined it. But Beauregard’s conclusions challenge this consensus.

Naturalism and free will

Are most naturalists determinists?

The logic is difficult to escape. If the natural world is all there is, then only natural causes, effects and laws can be effective in everything that happens. This extends to human choice. Our brain states, like everything else, are determined by antecedent conditions and natural laws. We can do little to control most of these, in fact, there is no “us” outside of these physically determined processes in the brain. Any control we exercise is itself determined by antecedent conditions and natural laws.

It can be argued that there are random events with no apparent causes, for example, atomic decay and quantum effects. Those who believe these effects may operate in the human brain can say that everything is either determined or random. A second argument looks at the mathematics of natural laws, showing that there are many situations where the equations become indeterminate. But while these two ideas avoid rigid determinism, neither of them provide for libertarian free will, for random is no more free than determined.

It appears that many scientists and philosophers are determinists. However according to the SEP, a growing number of philosophers are not determinists. Other sources suggest that many believe the question is not resolved.

Determinism and free will

Here the waters get murkier. At first glance, you would think that determinism implies no free will = incompatibilism, on the basis that if antecedent conditions together with the natural laws determine our behaviour, there is no place where we can initiate anything we do. Our choices are simply what we have been determined to choose – we couldn’t have done otherwise. Thus Prof William Provine:

Naturalistic evolution has clear consequences that Charles Darwin understood perfectly. 1) No gods worth having exist; 2) no life after death exists; 3) no ultimate foundation for ethics exists; 4) no ultimate meaning in life exists; and 5) human free will is nonexistent.

Other incompatibilists include Sam Harris, Jerry Coyne, Alex Rosenberg and many neuroscientists and social scientists.

But this conclusion is opposed to our experience, where we seem to exercise free will, at least on occasions. It turns out that the majority of naturalists I have come across are compatibilists. For example, at the recent Moving Naturalism Forwards workshop, the majority of the participants expressed compatibilist views.

Compatibilism

Compatibilist arguments typically consist of formulating a step-by-step logical argument for incompatibilism, and then disputing one or other of the premises. Thus they undermine incompatibilism, and as the two views are each the negation of the other, they attempt to establish the truth of compatibilism.

However, to follow this path tends to require a re-definition of free will. For example, many compatibilists define free will as freedom from external compulsion, which is only a part of the definition we started with, and ignores the more natural meaning of being able to have chosen otherwise.

For many philosophers, the problem is insoluble, some say meaningless. Thus the Moving Naturalism Forwards workshop concluded that discussing free will was “a philosophical black hole” and suggested that the term “free will” should be replaced by “voluntary” and “involuntary”, which is an example of re-defining the concept.

Philosopher Daniel Dennett is a strong proponent of compatibilism. I have read two of his books on the topic (Elbow Room and Freedom Evolves) and was unable see any explanation of how a deterministic universe allows free will. Instead it seemed he was merely dissolving the problems of free will. (A review of the book on Amazon summarised his approach as: “certain questions cannot be asked or at best do not make sense. The job of the philosopher is to find those questions and expunge them”.)

Non-determinism and free will

If the world is non-deterministic due to quantum or other uncertainty, free will is just as problematic. Actions which are uncaused, unpredictable and apparently random cannot be said to have been chosen freely any more then determined actions.

Looking for an explanation

In the natural world, we look for explanations. For example, if we can prove a certain result statistically (for example, that there is a very high incidence of cancer in a certain location) we then seek explanations of why this is so. It seems to me that the same is a reasonable request for free will. How does choice actually occur in the brain?

Incompatibilists can provide such an explanation, in terms of neuroscience. They can point to experiments such as those conducted by Libet, that can be interpreted as indicating that none of our choices are made by our conscious mind, and therefore don’t meet the definition of free will.

(Some dispute that the Libet experiments should be interpreted in this way, and some point to the experiments by Wilder Penfield, which appear to show free will in operation, but nevertheless, the incompatibilist explanation is plausible.)

However I have never seen a compatibilist explanation of how libertarian free will is actually possible in a naturalistic universe. In every case I have come across, they have only provided arguments aganst incompatibilism, assertions and re-definitions as outlined above.

And it is easy to see why. If “we” (i.e. our conscious selves) are no more than the outcomes of various physical brain states, then what is there in our brains that can interrupt the physical processes? To initiate and cause a freely-willed action, the physical processes in our brains have to be able to some initiate themselves. There doesn’t seem any way this can happen if naturalism is true, and so this form of compatibilism seems to forever lack an explanation.

Many scientists and philosophers agree that we cannot have free will, for example:

You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behaviour of a vast assembly of nerve cells and their associated molecules.

Biologist Francis Crick

The impossibility of free will …. can be proved with complete certainty.

Philosopher Galen Strawson

The implications of determinism

Although many scientists and philosophers believe humans don’t have free will, most of them believe it is impossible for us to live with that belief. Philosopher John Searle: We can’t give up our conviction of our own freedom, even though there’s no ground for it.

Belief in determinism is virtually impossible to live with for several reasons:

• We appear to be made that way and cannot think any other way. Cognitive scientist Marvin Minsky says of free will: Too much of our psychology is based on it for us to ever give it up. We’re virtually forced to maintain that belief …. Physiologist Colin Blakemore: The sense of will is an invention of the brain.
• The importance or otherwise of free will is a much-discussed question for law and psychiatry, where people may be held responsible for their choices. Philosophers and the law tend to think free will and mental health are required for moral responsibility and just justice, but psychiatrists are not at all agreed. Chief Judge in Equity, Supreme Court of New South Wales, David Hodgson, writes: Our system of criminal justice is based in various ways on common-sense ideas of free will and responsibility for conduct, but many psychiatrists are arguing this should change.
• Philosophically, it is difficult to explain rationality if we have no free will. To be rational, we must be able to decide on a course of action based on our assessment of truth, but determinism says our actions are determined by physics. John Searle: In order to engage in rational decision making we have to presuppose free will
• Studies show that when people stop believing in free will they are more likely to behave unethically. Scientific American: when people believe – or are led to believe – that free will is just an illusion. they tend to become more antisocial. Thus Philosopher Saul Smilanski believes that free will is a morally necessary illusion, that is, it is vitally important …. to maintain or promote crucial moral or personal beliefs and practices.
• Belief in free will is necessary for us to be ethical and human. Edward Slingerland: There may well be individuals who lack this sense [of feeling they are free], and who can quite easily conceive of themselves and other people in purely instrumental, mechanistic terms, but we label such people ‘psychopaths’.

Dualism and free will

The alternative viewpoint to naturalism is dualism, which in essence is the belief that there is more involved than what can be considered “nature” and open to investigation by science.The mind is seen as non-material and different from the brain, though dependent on it, and free will resides in the mind. For example, philosopher David Chalmers suggests matter is not all there is – consciousness or experience is a fundamental fact of the universe, just as magnetism and gravity are. Strictly speaking, this view may not be dualism, but if not, it is very close.

Clearly dualism has some advantages and disadvantages as an alternative explanation. It is not supported by current science, indeed it cannot be, because current science assumes naturalism and so can only measure the natural. But it does provide an explanation of free will, which accords with how we seem to experience it, which naturalism, via either compatibilism or incompatibilism, seems unable to do.

There are few dualists in philosophy, even fewer in neuroscience. Dualism is often associated with religious thinkers, but there are also atheists who are dualists.

Conclusion

There seem to be five possible views on free will:

1. Free will is not possible, because all events are either determined or random (incompatibilism). This provides an explanation that fits with science but does not accord with life and choice as most of us experience it.
2. Free will is possible provided we re-define it (one form of compatibilism). This effectively becomes the same as #1, but using different words.
3. Free will is possible even though the world is determined or sometimes random (another form of compatibilism). This accords with human experience, but how it occurs cannot be explained and cannot be verified by science. It thus seems to be a statement of faith.
4. Free will is possible because the natural world consists of more than the physical (dualism). This accords with how we experience life and choice, and can be explained conceptually, but cannot be verified by current science, and is thus to some degree based on metaphysics and experience.
5. Free will is possible because a personal God created the natural world so we are both physical and immaterial/spiritual (dualism). This too accords with how we experience life and choice, and can be explained conceptually, but cannot be verified by current science, so is also based on metaphysics and experience.

Which view is correct?

If views that deny or limit free will are true ….

…. it is hard to see how we can hold people morally responsible for their actions. We would have to alter some aspects of our legal and criminal justice systems, and take a different view of ethics. Ethics are already problematic under naturalism (see How do we know right & wrong?), and this would make it even more difficult to justify ethical judgments on others.

But it seems that such a view is almost impossible to live consistently without losing our humanity. Psychologists say we need to believe in free will. This creates an interesting dilemma.

An unavoidable dilemma

Science is based on naturalism – even scientists who are not naturalists apply methodological naturalism in their science, that is, they look for naturalistic explanations because that is what science does. But naturalism is an assumption.

And this assumption leads to the conclusions discussed here: that we have no libertarian free will, but also that we cannot live and be ethical human beings without believing we have free will. We are forced to believe our minds are misrepresenting reality to us and to live believing an untruth – all because we have made the assumption of naturalism in our science.

What if we trust our experience?

We recognise we cannot prove that the external world and other minds are real. But all of us believe they are real because our experience of them is consistent across time, they are experienced by everyone, and believing they are real helps us live productive and meaningful lives.

But free will too is universally experienced, is consistent, and clearly helps us to live meaningful lives. So there is good reason and good precedence to trust our experience of free will, at least provisionally, and not just jettison it because we have made assumptions about naturalistic science. Rather than privilege the assumption of naturalism, or the experience of free will, we should at least look for ways to re-examine them both.

Dualism

It seems to me, though not to some philosophers, that we can only have libertarian free will if we accept some form of dualism. Dualism cannot be proved by current science, but neither can it be disproved. Perhaps we need to re-examine our science, a view held by atheist philosopher Thomas Nagel and neuroscientist Mario Beauregard, who provides plenty of evidence that a new scientific paradigm is required. But I don’t see that happening any time soon.

Free will and God

We are then left with asking how dualism could be true. Philosopher David Chalmers offers a naturalistic answer by suggesting that matter isn’t all there is in the universe (i.e. he is a naturalist but not a physicalist), without explaining how the non-material consciousness could arise from natural processes which started with the big bang.

Fellow philosopher JP Moreland argues that theism is the best explanation – a non-material God created a universe which contains both the material and the non-material. Thus our experience of free will becomes an argument for the existence of God.