Riemann
November 14, 2016, 6:47pm
5
We had a discussion about this recently that arose tangentially from a QM thread, so I’ll post up some of what I wrote there to summarize the “no free will” argument. I’ve edited myself in a couple of places in square brackets to clarify.
I assume almost nothing [I don’t exclude supernatural processes, unknown to science], but however our decisions are made, they must be made somewhere. We can even allow the existence of mind-body duality, of a soul, [or some other supernatural process of unknown mechanism]… but for shorthand let’s use “brain” to denote the decision-making part of us. I only ask that we must be careful not to make the mistake of a combination of petitio principii and the homunculus argument , of assuming that there is some independent sub-entity within the brain with free will, because then it just reduces to asking how that sub-entity makes decisions.
So, [without speaking to physical mechanism] how are decisions produced? There may be random elements that may cause uncertainty and variation, but nobody thinks rolling a dice is free will. That leaves deterministic reasons . [Even if decisions are supernatural, of unknown physical mechnanism], logically, what else is there in any conceivable universe other than deterministic elements plus stochastic elements?
So, if a decision is made for reasons , how can it possibly be that precisely the same data input into a brain in precisely the same prior state can ever produce a different output (setting aside random variation)? It just makes no logical sense.
Moreover, there is simply no observable event that has ever occurred in the history of the world that corresponds to the notion of somebody “doing something different in precisely the same circumstances”, because we only get to run history one time. We have an incredibly strong internal illusion that we could have done something different if we re-ran history, but we have no evidence whatsoever to back up that illusion.
Thus, as I say, what is usually called contracausal or “spooky” free will - the notion that we could have done otherwise in precisely the same situation - is simply an incoherent concept. [Although there is no evidence for it, the principal] reason that it does not exist is not empirical. It could not possibly exist in any universe because at heart it’s nonsense.
The number of philosophers who believe in contracausal free will is to a good approximation zero [higher if you include theologians]. Yet, the vast majority of [ordinary] people still do believe in it, imo just because they haven’t thought it through carefully. Some philosophers (such as Dan Dennett) have written books supporting the notion of free will - but they have just re-defined it to mean something else, “lack of constraint” or whatever. Imo they distract from the important fact that what Christians and almost everyone else means by free will (the contracausal kind) is simply nonsense.
A common first response to this is to assert fatalism . If we have no free will, what’s the point in having this conversation, let alone a more serious discussion of the ethical basis for a justice system? If it’s all predetermined, why bother even thinking about it?
[First of all, there’s an element of this that is…] the appeal to consequences fallacy. [The knowledge that our free will is an illusion is disconcerting, and there may not be any completely satisfactory account of the implications, but the same is true of quantum mechanics, for example. The fact that something is disturbing and counterintuitive does not make it wrong.]
[If there’s no free will, can ethics still mean anything?] Well, perhaps “right” and “wrong” must start to mean something slightly different from our prior conception when we realize that free will is nonsense, but that does not save free will. We must simply rethink matters. In fact, I see no reason that the absence of free will negates ethics. If I kill someone, although ultimately I could not have done otherwise, it was still wrong to do it. A criminal justice system can still be either just or unjust , even if ultimately that criminal justice system itself (the product of our communal decision-making) could not have been otherwise.
But, ultimately… - if there’s no free will, why bother?
I think the best analogy is this: our visual system incorporates many illusions generated by our brain that allow us to interpret the world - we do not “really” see the continuous perfect picture that our brains tricks us into thinking we’re seeing. But, although it’s interesting to learn about this, it would be crazy to start trying to subsequently try to use our eyes differently for practical purposes. Obviously our visual system evolved that way because it works well.
Similarly, our brains developed the illusion of free will in decision-making. All that we are really doing is processing data and generating output, but perhaps the illusion of deliberation and agency leads to better decisions. Thus, as in the point you made earlier, even though free will is an incoherent idea and does not exist, it would be silly to try to actually fight the illusion of free will as we make decisions every day. I agree that the world seems strange and uncomfortable in certain ways without free will, but ultimately we just shrug our shoulders and get on with making decisions as best we can, including arguing for an ethical justice system.