Sean Carroll - Physics of Free Will

Free will has traditionally been a problem in philosophy. Recently, the battleground of free will has shifted to neuroscience. Now some claim that to solve the problem of free will, we must go far deeper, to the fundamentals of physics, down to subatomic forces and particles. But don't free will and physics operate at vastly different levels or size scales?



Sean Carroll is a Research Professor in Physics at the California Institute of Technology. His research focuses on fundamental physics and cosmology.


Closer to Truth, hosted by Robert Lawrence Kuhn and directed by Peter Getzels, presents the world’s greatest thinkers exploring humanity’s deepest questions. Discover fundamental issues of existence. Engage new and diverse ways of thinking. Appreciate intense debates. Share your own opinions. Seek your own answers.

[catherinemoore]

Great illustrative explanation of what is meant by 'turning round in circles'

[anthonycraig]

Carroll is one of my favourite physicist 👨‍🔬. Actually he is a true renaissance man.

[ivobar]

I like him. He talks fast and to the point

[mauricelevasseur]

Ouf! This is a real exchange of ideas. The type that you only see on this fabulous channel!

[Strelnikov]

I love starting my day with these videos.

[FalcoOnline]

This is a very interesting way to describe free will, but how does Sean Carroll reconcile "assigning responsibility to people who make choices" with "the wave function of the universe evolving according to the laws of physics"? Isn't this like saying that the position and the velocity of air molecules in the room are fully determined, but the room temperature could be anything?

[infinitemonkey]

That was funny. I agree with Kuhn that you can interpret what Carol was saying as free will not really existing.

[briandaniels]

Sean carrol and Brian Greene make physics exciting

[jayk]

These two always joust - I hope they enjoy it. I like them both

[exceptionaldifference]

Always especially enjoy the back and forth between Sean and Robert

[davegrundgeiger]

Sean Carroll is possibly the most lucid human ever, which he combines with infinite patience and excitement in his teaching. And props to Robert Lawrence Kuhn for his deep ability to elicit such conversations!

[paxsreekantan]

Brilliant. Clear thinking at its best!

[fancee_shmancee]

I didn't think Sean's position was really adventurous. How does he reconcile the experience of free will with the idea that there's nothing outside of physics to act on a situation? I do think he was suggesting free will is an illusion. I don't find the position very interesting.

[justwatermoving]

Beautiful exploration. "...it's not an illusion anymore than temperature is illusion. An illusion is something you think is there, that's not there." "They don't find it useful to use free-will language." I love thinking about how somehow the 'big bang' birthed two people discussing free-will and whether 'it' exists or not.

[BulentBasaran]

Sean's latest book is on the foundations of quantum mechanics: Something Deeply Hidden. There he admits that those foundations are not only mysterious, but many physicists are encouraged, nay, almost forced, to not dig there. We don't know where the ground is. The wave function that's supposed to model it all has imaginary parts (complex numbers are very useful, but they are not real! :-) And gravity is not accounted for. Our subjective experience, our deepest reality, is beyond what physics can explain, so far. That's why we need good philosophers like Socrates, Democritus, Plato, Aristotle, Descartes, Spinoza, Hume, Kant and more...

[lokayatavishwam]

So he's basically giving a descriptivist outline of free will, as a behavioral feature of human beings that justifies some utility in assigning responsibilities to individuals in a social context. He was right in saying that it's a bad idea to ask a good physicist about free will, since it will almost be heretical for them to talk about free-will when they start from a materialist logical premise (which rejects the possibility of there being an immaterial cause). But a good philosopher will never cede totally to any one class of theories to dogmatically reject other potential theories that can inform our daily life practices. This is why it's not totally pointless (for a common man) to even talk about free will as a fundamental feature of reality. Or at the least, scientists can engage with arguments related to reverse-causality (i.e., the emergent whole being able to affect the constituent parts) to account for domain adequacy of different sciences. Example: Changes in mental state can affect bodily processes(wherein this change can be produced by self-reflection and the desire to reorient oneself in life). Without this possibility, psychology and other related disciplines will have no real basis to justify it's internal practical logic.

[a.gwhiteley]

People often use the term "emergent" without considering what the word means. A property - such as consciousness and free will - can only "emerge" in the material universe if it is already in some sense present, just as the form of a crystal emerges from the underlying molecular structure of the substance. The mole emerges from the molehill only if it's already in there! Sean's position is essentially a form of compatibilism whereby we sort of don't have free will, but also we sort of do - a "quagmire of evasion" as compatibilism has been described. Robert is right to say that Sean is really denying free will, but there is a huge difficulty here - for if we are seriously saying that all our thoughts are determined by the mindless forces of the material universe, then we cannot know any of them to be true or false, since we could not have thought otherwise. This means we cannot know our denial of free will to be true or false either. Put another way, if determinism is true we can never know it be true, since all our thoughts are determined - including determinism! The denial of free will is the denial of reason, and therefore ultimately of the science Sean so rightly values. I'm afraid we do have to give serious consideration (as so many great scientists, including Schrodinger, have done) to the concept of consciousness as a fundamental aspect of reality, not as an incidental by-product of mindless material forces.

[georgegrubbs]

If "free will, " the ability for humans to make choices, is determined by the underlying details, then how can we be held responsible when the underlying details, controlled entirely by physics, caused the choice to be made?

To get to the bottom of the "free will" question, we need to know: (1) The neural circuits (networks) that cause a choice to be made, (2) The mechanism, that we refer to as "me, " that actually "makes a choice, " (3) The answer to, "Are emergent phenomena free from those processes that cause it? (4) Answer, "Can the "me" circuits override the deterministic neural chain of events?

That's a start.

[jamesc]

The view being discussed here is known as "compatiblism" or "soft determinism". It's basically the view that we don't have to abandon the language of agency if we discover we're deterministic. Just as the thing we referred to as "the Earth" when we thought it was flat we continued to refer to as "the Earth" when we discovered it was round, and the things we referred to as "stars" when we thought they were little points of light we continued to refer to as "stars" when we discovered they were giant balls of gas, so to the things we referred to as "acts of free will", "choices", and so on, when we thought they were indeterministic we can continue to refer to as such if we discover they're deterministic. Our understandings of them may have changed, but we're still referring to the same things.

[stephengee]

I would define free will as consciousness affecting matter and energy through the mind having some minimal control over thought patterns and body movements. Driving cross country is a prime example of cognition's ability to control the movement of matter and energy in a non random way.