• Question: atoms and particles act in probabilistic ways and our brain is made up of atoms and particles, so is there such thing as free will??

    Asked by josh to Alan, Caspar, Diana, Murray, Sarah on 17 Mar 2011 in Categories: .
    • Photo: Alan Winfield

      Alan Winfield answered on 13 Mar 2011:

      Hi Josh

      Wow that’s a very good question and it so happens it’s something I’ve thought about quite alot.

      You’re quite right to say that atoms and particles act probabilistically. They have random properties – Heisenberg’s famous uncertainty principle states that if we measure one property of, say, an electron, such as its position then we cannot also measure its momentum, and vice-versa. And since brains are made of atoms and particles then surely it follows that these are probabilistic systems. The probabilistic nature of atoms and particles gives rise to a kind of noise – if you turn on your stereo without a CD in and turn up the volume you will hear noise from the speakers – that’s because the molecules in the electronics of the stereo system are hot (and vibrating in ways that cannot be completely predicted according to Heisenberg).

      I personally think that we humans do indeed exercise free will (but some scientists say there is no such thing as free will – it’s a controversial question). However, I think that humans (and animals in general) truly exercise free will rather rarely – much less often than we like to think we do. But to return to your question – my theory (and I can’t prove this) is that it’s because brains are noisy that we can have free will. Let me explain this as follows (I’m going to talk about animals – but I think the same applies to humans.)

      Consider this ancient choice: fight or flee. Most of the time, for most animals, there is no choice. The decision is easy: the other animal is bigger, so run away; or smaller, so fight; or it’s bigger but we’re trapped in a corner, so fight anyway. Most of the time the choice is determined by the rules and the situation, or the environment – so free will is not needed.

      But occasionally the choices that present themselves are perfectly evenly balanced. The animal still has to make a choice and quickly, for the consequences of dithering are clear: dither and most likely be killed. So, how does an animal make a snap decision whether to fight or flee, with perfectly balanced choices? The answer, surely, is that the animal needs to, metaphorically speaking, toss a coin. On these rare occasions its fate is decided probabilistically and what I call neural noise will tip the brain into making a snap decision when all else is equal – the neural equivalent of tossing a coin.

      This is why I think free will relies on noisy brains, and brains are noisy because of probabilistic atoms and particles.

      Please let me know if you think this answer makes sense!

    • Photo: Caspar Addyman

      Caspar Addyman answered on 14 Mar 2011:

      probably

    • Photo: Diana Drennan

      Diana Drennan answered on 16 Mar 2011:

      ah, very philosophical… I think I choose to do things, or not to do them. I don’t believe things are predetermined, nor do I believe in fate. For instance, I didn’t HAVE to answer this. Although, given my personality and the venue it might have been predicted…you could not have said with 100% certainty – “she’s going to answer this question and say this particular thing” There is uncertainty in what people do, and uncertainty in what an atom or particle is going to do, too. we can say where it is most likely to be, but not 100% certain. Perhaps the key to your question is the word “probabilistic”. I will “probably” answer, but it’s not certain. Therefore, I have free will.

    • Photo: Sarah Thomas

      Sarah Thomas answered on 17 Mar 2011:

      Oh Josh, this question has been bugging me all day and although philosophy is not my forte, i’m going to tell you what i’ve been thinking about it.

      Ok so, I see what you mean about atoms behaving in a predictable way, we’re made of atoms so can you predict our behaviour? And there’s 2 conclusions I’ve come to:

      1) Atoms and particles may not behave in probabilistic ways. They appear to act in predictable ways, and we make loads of equations to try and map them and understand them, but the ways in which we can make observations are so limited! We can’t even detect dark matter and that’s supposed to make up 25% of the entire universe. When we say, “that atom is probably going to do that” we are actually saying, “there is a chance that atom will do that, but it could do something totally inexplicable and random”.

      2) I believe we are made of more than just atoms and particles. The way all those atoms in your brain fit together and work together, is amazing. Neurons firing, memories being stored, optics – how is all that even possible?! There is more in your brain than just matter.

      We have free will, and we can break whatever laws we want, be they physical, chemical, electrical, or quantum mechanical.

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