By the way, there's a pretty nice recent article on the topic by Steven Weinberg in, of all places, the New York Review of Books: http://www.nybooks.com/articles/2017/01/19/trouble-with-quantum-mechanics/

It would be nice to give you a link to a good technically-oriented overview, but so far I haven't found such a thing.

No worries! There is so much hogwash peddled as implications of quantum theory it's not too surprising anyone with real physics experience would tend to shoot from the hip :)

Thanks for the reply, and the welcome! This is an interesting but difficult question (which is why I like to stick with the somewhat simpler question of practical implications).

First, it's very hard to even ask the question in a rigorous way. If you get technical about it, defining what's meant by "one" (as in "does one have free will"), or "consciously", or "agency" is quite a non-trivial problem. Under the eliminative materialist view, such a phrase can be argued to be simply incoherent, resting on "folk psychology" that leads us to believe in various illusions about ourselves (such as that we are conscious in the first place!). This is the angle that Daniel Dennet generally takes, and is probably (though I'm not certain about this) a factor in the reframing of "free will" under compatibilist accounts, and in claims that the question of free will has been "dissolved".

My personal opinion is that it is very likely we do posses a form of conscious agency (in the intuitive sense of what this means), but that established science would have to be modified in alarming ways before we'd be able to understand how it could work. The background for this opinion involves a chain of reasoning that is very long, circuitous, and speculative, so probably beyond the scope of this discussion :)

Hi Devac,

I'm the author of the blog post in question. I am not a physicist, and I wouldn't claim to know that much about physics. However, in this case I'm not entirely ignorant.

As John von Neumann, Erwin Schrodinger, David Bohm, Scott Aaronson, Max Tegmark, Anton Zeilinger and many others have noticed, the ontological issues with quantum mechanics are much more serious than a problem of interpreting complex mathematical constructs with brains that are "unequipped to that type of thinking."

While I'm sure your knowledge of physics is superior to mine, knowing how to do physics doesn't guarantee knowledge of the bigger questions that surround it -- a fact that is much less obvious but just as true as the reverse. Even professional physicists are not necessarily aware of the philosophical problems with quantum mechanics (though that wasn't always the case. See this paper from European Journal of Physics for an interesting look at perspectives on the subject among the originators of quantum theory). For an overview of these questions from a philosophical perspective, see the Stanford Encyclopedia entry on the topic.

If I understand correctly, I think you took my comments about ontological issues and QM working "for all practical purposes" as referring to whether approximations are required, or the relationship between QM and relativity. This wasn't my intention. Instead, I was referring to what I think you called, rather charmingly, "technicalities about measurement". In other words, the measurement problem, which is a key motivation for the many conflicting interpretations of QM.

The various interpretations are really not "just interpretations", or epistemic claims. They are mutually incompatible accounts of what really exists in the physical universe. Everett's "many worlds" interpretation, for example, says very different things about the nature of physical reality than Bohmian Mechanics or Penrose's Objective Reduction account. These are called "interpretations", but they imply greater uncertainty about the fundamental facts of the universe than most other questions that are considered to be within the domain of science. That's what I mean by an ontological discontinuity in the basement of physics. It's ontological because it has to do with the nature of existence. It's a discontinuity because there's no generally accepted and principled way to reconcile reality as described by unitary evolution of the wavefunction and reality as observed and experienced. And it's in the basement because many people, even in physics, aren't aware of it or would prefer not to think about it (also because it's connected to the research area known as "quantum foundations").

Anyway, I hope this rather late reply at least convinces you that I've read something other than Wikipedia on this topic :)

ThatFanficGuy,

I know this question is many months old, but maybe as the author of the post I can at least provide one version of an answer.

As far as I'm aware, challenges to free will from established science come in two forms. The first is the obvious one: if the state of the physical world is dependent only upon 1) the previous state of the physical world and 2) probabilistic effects of quantum mechanics, then all our actions and the brain states that lead to them are the result of these two factors, which we (in the usual, subjective sense) are powerless to change or influence in any way.

The second challenge is more empirical. Beginning with Libet in the 80s, many studies have shown that what we perceive as "our" conscious decisions are in fact made by our brains well before we are aware of them. See for a recent and competent example this paper from Chun et. al. in Nature Neuroscience and the references in it.

I wouldn't say by any means that science offers proof of the non-existence of free will. Proof of the non-existence of anything is a dicey business, and might not be possible even in principle in this case. What I would say is that established science -- taken as both the results of experiments and a more general perspective regarding the nature of reality that is influenced by but not strictly derivable from those results (ie, materialism) -- leaves very little room for free will under any particularly meaningful definition of the term (of course, if established science were to change, this could change as well). More details in my reply to Odder.

Adam

Odder,

As the person responsible for the article, I hope I'm at least qualified to (very belated) enter this debate!

I'm not ignorant of compatibilism, but to me the version of "free will" accepted under it seems mostly meaningless. To me it seems that compatibilism is a project of academic philosophy that creates a whole new argument which, while supposedly about "free will", is in fact more about the definition of terms, turning the topic into a good example of a verbal dispute (see this helpful paper by David Chalmers for a good commentary on verbal vs. factual disputes).

What I'm saying in the post is that we don't need compatibilism. Compatiblism was invented in order to squeeze some kind of moral responsibility into a causally closed physical world (as the Stanford Encyclopedia entry makes fairly clear), in an era before most of what we now know about psychology and the measurable aspects of human nature. At this point, I think we can simply delete the idea of punishment and reward as a consequence of moral agency and -- guess what -- hardly anything (of practical relevance) changes!

So, the entire article was in a sense "respond[ing] to the idea of compatibilism" (by questioning the motivation behind it). As a blog post, rather than a paper, it didn't seem necessary to pepper it with academic jargon for the sole purpose of showing that I have read the right books, know the right words, and have tried on the right opinions to enter the debate!

That said, I admit that publishing anything under a header that includes the word "autodidact" could be taken as an invitation of suspicion regarding the author's competence.

Regarding the suggestion that I might be claiming to have "disproven" free will, see my response to the initial question by ThatFanficGuy (or, for that matter, the original blog post!).

On a side note, for a curious and different take on free will (as well as various things about QM and other interesting stuff), check out The Ghost in the Quantum Turing Machine by quantum computing bigwig Scott Aaronson.