How Science Proves That Free Will Does Not Exist, And Why That’s So Important.

Header image for article about how science disproves free will – there field only has one path that we can choose, so it it actually a choice?

What does it actually mean to say that human beings possess free will? Does it just mean that there are no constraints put on us by others, or does it mean more than that?

For the purposes of this article I’m going to assume that, when people say they have free will, what they mean is that they are the final authority on which pair of socks they put on in the morning. They really do face the possibility of deciding between two equally available options.How science proves that free will does not exist and why that's so important

Okay, so now that we know what free will means, we are somewhere along the way towards working out whether we have it. Let’s assume that we do. What does this mean? Well, put simply, that the the cause of my decision was me, and that I was not forced by anything else outside of my control.

So you might be thinking, of course I am the final authority on which hot beverage I choose in the morning! There is nobody standing with a gun to my head forcing me to choose coffee; I just feel like drinking coffee. Well then let us look at what is so problematic with this version of events.

Do We Have Free Will?

Free Will & The Non Physical Mind

Firstly, let’s get one thing clear. Either the ‘me’ (or ‘soul’ or ‘self’) that is choosing between coffee and tea is physical or it is non physical. Whichever you believe is unimportant, as I shall discuss both, but for now let’s assume the the self is non physical.

In order to understand this argument I should first lay out the Law of the Conservation of Energy, which states that there has always been, and forever will be, a constant amount of energy in the closed Universe, as it can neither be created nor destroyed. Of course, the Universe is physical, and so we must conclude that the soul lies outside of this Universe. No problems so far…

Now, for the non physical soul to cause things to happen in the physical universe, it must causally affect them – in other words, it must inject them with energy (without an energy transfer there is nothing to realise the effect). This, as we know, is not just conceptually a very challenging thing to imagine. It breaks the unbreakable Law of the Conservation of Energy. Therefore, given that this law holds at all times, a nonphysical self can never be the source of any free will. If you believe that we have a soul in the traditional sense, you now believe in a deterministic Universe, right? If not, leave a comment below as I’d love to hear your thoughts on this line of argument!

Never fear Free Willies, for there is still the possibility of a physical self being the cause of my actions! Remember here what we said earlier. In order to be free my decision must not have come from anything or anywhere outside of myself.

Free choice over which door to take

Free Will & The Physical Mind

Okay, so we have retreated to the concept of a physical, but free, mind. There’s another scientific law known as the Law of Cause and Effect, which might find fault with this idea. The law is very simple. It states that for every effect there is a definite cause and, likewise, for every cause there is a definite effect.

What this means is that everything in this Universe is caused, and every cause is itself and effect caused by a previous cause. There is nothing that is the cause of its own existence and there is no such thing as an uncaused cause. Therefore, given that the constituent parts of the self are physical, they are in turn caused. Something caused my preference for coffee, which in turn caused my deciding to drink coffee. The cause of my decision to drink coffee this morning was entirely based on the cause of my preference for coffee (maybe the smell of coffee beans). This meas the cause of my decision to drink coffee was external to myself, i.e. the decision was not my own.

Here you may say well hold on there! Of course the outside world is able to influence our  decisions – it does so all the time! I prefer eating bread to chicken because of the fact that chickens have to suffer so that I can eat them. Reality influences my decision but the decision is still freely mine!

Ahah! You’ve fallen straight into the trap which has led so many people to trip up. The question is no longer whether it was me that decided to choose coffee (regardless what influenced me). The question is whether or not I was utterly free to choose tea. I put it to you that the decision to drink coffee was entirely mine. However, the fact that the things which caused the conditions in me conducive to my choosing coffee have already happened means that there’s simply no way for me to rebel against the unwavering law of cause and effect and choose tea. The path was laid out in front of me with nowhere to go, and all I had to do was walk down it.

I hope you can see here that this is not freedom – this is nothing like freedom. Therefore there must not be any way for a physical self to be called free. But wait a minute? Didn’t we just say that there’s no way for a non physical self to be called free either? What does that leave us left with?

Oh yeah, that’s right – we’re left with the only possibility being that neither non-physical nor physical selves can be the rightful arbiter over our actions. Legitimate freedom then, in the sense that we wish to use the word today, is an illusion.

Take a moment to think about the wide ranging and severe consequences of what determinism might mean. This conclusion calls into question the very nature of morality, of punishment, of justice – of why we even bother.

What do you think about this argument? Have I convinced you? Leave a comment below as I’d love to hear your views! Don’t forget to keep your eyes peeled for the next article coming up, in which I discuss the idea of a deterministic Universe, and what that means for us all.


In the meantime, why don’t you check out The Philosphere on Twitter?

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  1. Perhaps the soul doesn’t apply to the Law of Conservation of Energy? This is a hypothesis that most likely will never be proven, but a possibility. Perhaps one’s soul is simply a physical dimension of this world we have yet to scientifically understand? None of this though successfully placed a point to life..

    1. You’re right Jonathan I agree that the Law of Conservation of Energy is a contingent one, but to say that one fundamentally ‘weird’ thing can apply outside of it as a nomological dangler it to retreat into a mysticism and I don’t think that can ever be a valid position. For a hypothesis to be meaningful it has to at least be, in theory, falsifiable.

      Would you agree?

  2. Graeme,

    Thanks so much for taking the time to critique my article – that is after all why I write them! Before I discuss the points raised above I’d like to say that you clearly know what you’re talking about which makes discussion far more enjoyable.

    Ok so over to your rebuttal of my argument. Firstly, to address your ‘tangent’, in posing this argument I am not meaning to promote the claim that the self is non-physical. What I was meaning to do was prove why Free Will is impossible if the soul is non-physical, then prove why Free Will is impossible if the soul is physical (thereby proving that Free Will is impossible in any case).

    Looking at your standard form representation I don’t believe you have straw manned me at all. However, I don’t agree with your fault. I do not believe that there is any flaw in stating that for X to have been effected by Y then Y caused X. This is simply the analytical relationship between cause and affect which is not subject to debate. Therefore, it is sound to reason that, presupposing that Free Will exists, the non-physical self causes things to happen in the physical Universe. Now, every cause is fundamentally seated in some form of energy – energy is inextricably linked to the effect such that you cannot remove the energy without removing the effect. This is akin to removing the cause without removing the effect which is logically impossible (the energy is the cause). Therefore, I see no logical alternative other than to conclude that chains of causation involve the transfer of energy, and that for the mind to effect the body would involve the transfer of energy, and allowing that the mind is outside of our closed Universe would mean that Free Will entails increasing the level of energy in the Universe infinitely. This is of course not the case and so Free Will is false.

    I fee like I haven’t been completely clear but does that summarise my position any better?

    Do let me know. Thanks again!

  3. Hey there James! Interesting article, something that has alway interested me in my studies and free time (haha free time, theres a concept for you.) Anyways, I do have argument with you in regards to your first concept, that of free will, or lack of, and a nonphysical soul.

    If I may be so bold as to put your argument into a syllogism:
    1. The law of conservation of energy states that energy must be constant in the universe.
    2. The non-physical soul/self is outside of this universe.
    3. In order for the soul/self to influence the universe it must causally affect them (inject them with energy)
    4. However, if the soul/self affected the universe causally, it would break the law of conservation
    5. Therefore the universe cannot be affected by a non-physical soul and must be deterministic.
    (Pardon me if this syllogism seems incorrect, I am not trying to make a straw man out of your argument, feel free to correct it.)

    My problem with this argument comes in at point 3. Since you have just established that the soul/self is outside of this universe* it seems a rather rash assumption that in order for the soul/self to affect the universe it must do so causally. You have put the soul outside of the universe and therefore outside of the rules of the game so to speak. Why should it conform to our rules if it has just been placed beyond them. What we are encountering here is the perennial mind/body problem. How a non-physical mind affects a physical body is a complicated question, one with many posed answers, yet it is still open, and I do not believe that you have solved it with your claim that the soul “injects energy” to create a causal affect in the physical universe. I believe you are making the assumption that the non-physical soul outside of our universe is still physical but outside this universe. How else could it cause energy to affect. It is as if you are saying that it comes in from another dimension and affects this dimension through some unbeknownst cause and affect system. But this still leaves the question open, how can a non-physical soul/self be the source of free will? This I cannot claim to know.

    Let me know if you have any thoughts on this.

    Graeme Thompson

    (*On a slight tangent I must say that it is a very strange concept indeed, I prefer to think of it within the universe but slightly beyond our comprehension or ability to measure. Such as how we cannot see the entire spectrum, however there are other waves out there beyond our vision. Back before we could measure them with instruments, if someone had proposed the idea of x-ray, or gamma rays, it would’ve been similarly “beyond our universe” but then as we progressed it came into our universe so to speak. Similarly with the soul, perhaps it is just beyond our measurement at this point. Anyways, let’s stick with it being outside of the universe, it changes the argument otherwise.)

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