Free will. Do we really possess it?

The existence of free will (or lack thereof) has been the source for much discussion in philosophical and scientific circles for centuries. Division appears to separate participants into three primary schools of thought: determinism, compatibilism (also referred to as soft determinism) and libertarianism. This essay critically analyses free will and causal determinism against the backdrop of modern science, finding that despite our universe being indeterminate, there remains little grounds to conclude that free will exists.

As mentioned, arguments concerning free will can be classified into one of three camps. Determinism rejects the notion that we can exercise any form of free will and asserts that all our actions, thoughts and cognition included, are causally necessitated. Contrary to this, libertarianism rejects causal determination by allowing free will to exist, whereby we can choose our actions and the future is not fixed until such choices have been made. The third group, compatibilism, takes the middle ground and seeks to reconcile the two, though seemingly through semantics as opposed to truly marrying ideals.

Firstly, no solid consensus on what constitutes ‘free will’ appears to exist. Intuitively it refers to where rational beings exercise control over their thoughts or actions which does not arise from causal necessity (where you physically could have done something other than what you chose to do). Compatibilists like Hume and Hobbes propose another interpretation, that you exhibit free will so long as you are not forced by another person into your action. For example you would not be considered free if someone were to force you to do something, however you would be considered free if you were not so inhibited, even though your actions were entirely predetermined. To avoid such linguistic loopholes this essay will look at the former definition for free will.

Hence:
1) for someone to exhibit free will, their actions could not be perfectly predicted (in theory or in practice) to a degree greater than assigning probabilities to their possible actions. 

It is obvious from this definition that free will is the basis for moral responsibility and our legal system. Without it the actions you perform should attribute no praise or blame upon you as you had no option but to perform them. Criminals may still need to be detained for the safety of society, but further punishment seems morally wrong as they had no power or control over their deeds. It is therefore important to consider whether humans possess free will and are morally responsible for their actions or not. According to Scottish philosopher David Hume, it is “the most contentious question of metaphysics, the most contentious science.” (Hume 1748)

The question then is: firstly, do we live in an entirely determinant world? If so the question of free will seems moot, but if indeterminate actions occur, then does free will actually exist or is it still yet a cognitive illusion? It is important to note that indeterminism is a necessary, but not sufficient, condition for the existence of free will.

The required intuitive belief in free will and a deterministic world

Let us now examine the human notion of free will. I posit that the concept of free will, at the very least, is necessary to live as we understand today. We operate with the fundamental belief that we have power over our behaviours, thoughts and actions.

Suppose a shop assistant asked if you would prefer a red or green shirt. You could hardly respond “I’d rather wait and see what I decide because I know that my choice is already determined.” The illusion of choice must still be present for you to operate. Even if logically you conclude that you could not have done anything otherwise, you would still be required to act and ‘choose’. As Charles Campbell remarks, “no one … can help believing that he enjoys free will” (Campbell 1963).

Equally it appears impossible to operate without employing a level of determinism. It seems implausible to act without having some expected result in mind. Without causal determinism, such an assumption would be ludicrous. Just as you cannot refuse to choose or act and instead wait to observe your predetermined action, you cannot seemingly make a choice without an expected consequence in mind. You buy a car because it will hopefully allow you to get to places faster than walking, at no stage do you buy a car without an expected benefit. Instinctively we run away from a lion because we expect that if we had not we wouldn’t last very long! An expected outcome is essential to choice, whether it also be illusory or not.

These two observations lead us to a fairly obvious contradiction in our decision-making processes. One cannot be both causally free in order to make decisions and yet need a deterministic universe to make the choice in the first instance (without introducing dualism which shall be touched on later). Nevertheless our behaviour appears to require at the least the presumption of both free will and causality.

The reality (or not) of determinism and free will

Having observed the need for both free and deterministic behaviour let us now move from intuition and gut feeling and look instead at theories not reliant on personal human experience.

Newtonian science has no room for indeterminacy or free will. French mathematician Pierre-Simon Laplace suggested that if a sufficiently advanced intelligence knew the exact location and momentum of everything in the universe, then it could predict the future using Newton’s laws. Such a prediction is logically possible, albeit practically impossible, following Newtonian physics. Indeed “since every piece of matter in the Universe is in some way affected by every other piece of matter in the Universe, it is in theory possible to extrapolate the whole of creation — every Galaxy, every sun, every planet, their orbits, their composition, and their economic and social history from, say, one small piece of fairy cake." (Douglas Adams 1979). Free will cannot exist in such a deterministic, physical reality.

Contrary to Newtonian models, modern scientific theories do not support Laplacian determinism. Thermodynamics, developed in the 1800s, began to undermine the possibility of using current knowledge to predict historical events due to the irreversibility of some reactions. In the past century quantum theory has given rise to the acceptance of indeterminacy in the universe and appears to provide the final rejection of Laplace’s idea.

Quantum indeterminacy and the Uncertainty Principle which emerged early in the 20th century reignited the free will debate. As mentioned, scientific theory had previously pointed towards an entirely determinate universe – where it would indeed be possible to predict the future as Laplace posited. The issue with direct causality arises on a microscopic level where quantum indeterminism undermines predictability. The interaction of objects on a larger scale following Newtonian laws is merely the emergent property of an underlying indeterminate quantum system. When observing something travelling at very high speeds or anything smaller than a molecule, quantum mechanics comes into play. Without delving into specifics, it is impossible to forecast the behaviour of elements on such a scale because they do not follow a predictable pattern. Predictions can then only be based on probabilities.

Many philosophers view quantum indeterminacy in quantum mechanics as sufficient proof for free will. Superficially that appears possible but, as noted above, deterministic causality is still present on any reasonable scale. Linking the brain with quantum indeterminacy is then essential to a proposition of free will, and several avenues have been suggested:

1. The membranes at the end of axons of neurons are two molecules thick and hence indeterminism plays a role in neurotransmission ( Beck & Eccles 1992)
2. Microtubules which take part control in the state of the brain can have two different states depending on the position of just one electron (Corredoira 2002).

Though not experimentally substantiated as yet, these examples suggest the possibility that people are able to act in a partly indeterminate way. It is likely that the majority of actions could still be predicted on past experience and antecedent causes, but in much the same manner as quantum systems, variations from the normal are possible with their associated probabilities. Therefore: 2) our minds are affected by indeterminism

The argument for free will derived from quantum indeterminacy follows:

1. Free will is “by definition unintelligible” (Campbell 1963) – it need not follow a logical pattern lest it be causally determined; random uncaused actions constitutes free will.
2. Quantum indeterminism exists and our neurological state is affected by it

It then follows that:

3. Our actions are unable to be deterministically predicted
4. Therefore we are free                   - or are we?

At this level we are reduced to biological amplifiers of indeterminacy. This seems almost as unpalatable as a lack of free will entirely. Do we then accept this as free will or do we merely conclude that our behaviour is not just causally necessitated, it’s also partly happenstance?

                “So long as the prediction [of choice] does not pretend more than a measure of probability, there is nothing in our [libertarian] theory which would disallow it.” (Campbell 1963)

Campbell’s argument that free will is purely chance is seductive in its reasoning - for if free will exhibited in itself any strict reasoning then surely it would not be free? I feel that the failure in applying Campbell’s logic to derive free will from quantum indeterminacy is a lack of personal choice in any matter. Uncontrollable, random chance behaviour resulting from the interaction of the smallest constituents of our body is not personal choice and does not amount to free will. Without your overriding mind being able to select and discriminate in your thoughts, having indeterminate actions would be no more free than going through life making choices based on the roll of a dice.

Achieving true personal choice seems to still require a dualist approach to the situation. Dualism, as championed by Rene Descartes, is the belief that the mind (as opposed to the brain) is in some way nonphysical. An immaterial mind or soul impacting upon the decisions and actions of a person would certainly facilitate the requirements of free will. However there is little evidence to support (and many reasons to reject) such a conclusion, so we will also rule this out. At the very least Dualistic interpretations of the world do not sit within our current scientific picture.

To summarise, our behaviour requires the presumption of free will and determinism whilst the reality of the situation seems very different. There is now strong evidence for a degree of indeterminacy in our world, and yet despite this, very little to indicate that free will exists. Indeterminism and irreversibility now present in scientific theory give grounds to reject the Laplacian view of causal determinism in favour of a potentially indeterminate view of the world. Caution must be used to not immediately take this as sufficient proof for free will because, as shown, a free will such as that we suppose we possess would require personal control above mere chance.

Where does that leave us? The future of the world (to the best of current scientific knowledge) is not determined. If you could rewind and run the universe again from the beginning, one could assume from the indeterminate nature of its components that the resulting universe would be different to the one in which we find ourselves now. I agree that modern science does provide the hint of room for free will, however asserting any more than that is unfounded and would rely on a dualistic interpretation of the mind and body. 

This essay is copyright Andrew Barnes 2007. It may not be reproduced in any capacity without written consent. Please contact the author directly for any further queries.

Note from the author:
I hope that this piece has been interesting and stimulating. I unfortunately had very little time to be able to more fully delve into the philosophical and scientific issues, but it is certainly a beginning. Discussion is welcome.

Reference List:
Adams, D. (1979) The Hitchhikers Guide to the Galaxy, Pan Books
Beck F. & Eccles J. C. (1992) Quantum Aspects of Conciousness And the Role of Conciousness, Proceedings of the National Academy of Sciences, 89, 11357
Campbell, C. (1963) Has the Self ‘Free Will’?. reprinted Perry & Bratman 3rd ed, 417-425
Corredoira, M. (2002) Quantum mechanics and free will: counter-arguments. Journal of Non-Locality and Remote Mental Interactions, vol 1,3
Hume, D. (1748) Enquiry Concerning Human Understanding , Oxford: Clarendon Press, 1975
Taylor, R. Freedom and Determinism. reprinted in Perry & Bratman 4th ed, 451-463