A PBS Space Time video does an unconvincing job of discussing free will

November 15, 2020 • 11:30 am

I found this video from PBS Space Time, featuring Australian astrophysicist Matt O’Dowd expatiating on free will, to be singularly unenlightening.  While he seems to know his physics, and tries to use it to answer the question of free will—bringing in  both determinism and quantum mechanics—he winds up punting, saying that it’s a semantic issue and depends (of course!) on your definition of free will. But at the end, without having defined free will, he says that we can still say we have it because it’s an “emergent phenomenon” of our brain (“the most verifiably real phenomenon we can observe”), and, as such, is not an illusion.

But he mistakes what people like Sam Harris and me mean when we say free will is an illusion. Of course we feel we have choices, and often act as though we could have chosen otherwise—but it’s not clear if that’s what O’Dowd means by the “emergent phenomenon.” If it is, then it’s an illusion in the sense that it’s not what we think it is. Yes, we have that feeling of freedom, and that feeling is certainly real, but the illusion is that, as even compatibilists admit, we could not have done other than what we did at any moment in time. And, except for the action of any quantum events, the future is completely determined by the past.

Remember that, according to a survey of four areas by Sarkissian et al. (Hong Kong, U.S., India, and Columbia) between 65% and 85% of people believe that, at any moment, a person could have decided to do other than what she did. That is, a solid majority of people believe in a fundamentally indeterministic cosmos. Further, between 65% and 85% of the respondents say that if the Universe weren’t like that—if it were fully deterministic—people would have no moral responsibility for their actions.  It is these predominant beliefs that we must address if we’re going to have a sensible public discussion of free will. It won’t do to pretend that nobody believes in an indeterministic universe and its consequent libertarian free will, for that’s not true. And, of course, libertarian free will is an underpinning of all Abrahamic religions.

But I digress. I will add only this: O’Dowd seems hung up on predictability as an important part of free will. But all of us, including hard determinists like me, realize that we will never be able to predict human behavior with 100% certainty. Not only do too many factors impact our brains and behavior, but, as O’Dowd points out, the uncertainty principle bars us from even knowing certain fundamental properties of quantum-behaving particles (although those may have a negligible effect on behavior). But whether or not we can predict behavior seems to me irrelevant about whether or not we have free will.

At any rate, O’Dowd knows his onions, but I don’t consider this 13-minute video to be any advance in the question of free will.

h/t: Paul

45 thoughts on “A PBS Space Time video does an unconvincing job of discussing free will

      1. I guess Dowd do discuss the philosophic issue (I haven’t seen the video). He is all over the place – but he generally do a good job on the science.

        But else it could be said (if one likes sophistry) that philosophical discussions of free will – which has a quantum physics template (and so in principle should be testable) – do a lousy job miring the whole thing in abstruse philosophy.



  1. I think there are two definitions of free will here and that is the source of most of the controversy. O’Dowd follows the crowd that says free will and agency are emergent properties of the brain. At the risk of possibly putting words in their mouths, this is also the position taken by Dennett and Carroll. Free will is a term we use to describe our sense of agency, of being able to make our own decisions. It is an illusion if we are going to include fundamental physics in the discussion but we don’t do that except in philosophical discussions with Incompatibilists.

    Although free will is an illusion in the strict sense of the word, this doesn’t make it something that can be discarded as fake news. There are many things that are illusions but they are practical and we probably couldn’t function without them: the solidity of a chair, for example. We know it consists of particles with lots of space between them but we can ignore that as we sit down on it. Even the particles are an illusion. Physics tells us they are really fields that only collapse to particles if we try to measure them.

    Predictability of human actions comes into the discussion because if we could predict them from knowing the positions of particles and forces, they would overturn human life as we know it. There may be physics reasons we will never be able to do that but, even if there aren’t, there are practical reasons we will not overcome in the foreseeable future.

    1. That human life as we know it would overturn if human actions could be predicted – that may be so, but this dystopia is not at all the reason why the criterion of predictability entered the discussion about free will.The reason is another: non-predictability is used as an entry point for freedom and free will, the interface at which free actions are realized. In contrast to a completely determined universe where free will cannot exist.

      1. You really have to embrace the idea that there are (at least) two definitions of free will. Emergent free will doesn’t have much to do with determinism because it’s emergent, meaning it is a concept that only depends on the underlying physics as a substrate.

        It is well known that computation can be performed on a variety of substrates, not just silicon. You can do any computation that a computer can do with pencil and paper if given enough time and paper. If we consider a computation performed on a silicon-based computer, the answer it produces depends on the underlying physics. What about that same computation done with paper and pencil? Is it meaningful or useful to look at the underlying physics to figure out how the algorithm works? Of course not. Same for free will as an algorithm executed by our brains.

  2. This argument of the unpredictability of human behavior as parameter for or against the existence of free will is so senseless and superfluous.
    It is also not possible to predict 100 percent of weather events, not even the activity of the sun, or the spread of certain viruses across the globe. Would one therefore attribute freedom of will to the sun, the weather or a virus? No? But but for humans they like to do so.

    1. Your premise is incorrect. Unless I missed it, no one is offering unpredictability as an argument for or against the existence of free will. However, emergent free will would be rendered useless if we could predict human behavior from the state of the universe. Emergent free will would still exist as an understandable concept but impractical and inapplicable as an element of human culture.

      1. O’Dowd’s second “possible requirement for free will being real” is all about predictability. I don’t think sherfolder is creating a straw man. However, it might be that O’Dowd intends that second requirement not to be used alone, but together with some others.

      2. You really missed a big part of the discussion: Unpredictability is used as an argument for free will or at least as a kind of free will by philosophers, neuroscientists or even by physicists,
        For the astrophysicist Michio Kaku free will is simply the result of the unpredictability that arises from the influence of quantum processes. He labels the unpredictability with a new concept, which stands for freedom of will. In this way, he leads the discussion ad absurdum, because at the same time Kaku denies the possibility of being able to act otherwise.

        And have you never heard of the scientists who attest fruit lies a free will, because they would decide spontaneously and their behavior in an experiment was not predictable? Here is the link:


    2. I agree completely with your comment. The whole mess of philosophical re-definitions in this area is simply making it harder to communicate about what we all agree is the major issue: if the tape were rewound, could I do otherwise or not? And if so, is it due to something other than randomness?

      Dowd’s failure to distinguish weak and strong emergence is similarly grating. New rule: never use the word emergence by itself!

  3. Molecules and atoms don’t have appleness
    Therefore it would be a fallacy to say that some atoms and molecules are emergent apples. So, it could be a reductionist fallacy not to allow that free will might be an emergent property atoms and molecules. Really?

    Whether my will is a result of a fully deterministic mechanism, a random (quantum) mechanism or some combination. It still is a product of that mechanism.

    A mechanism for free will is an oxymoron.

      1. I think people wave around the term “emergent” as though it explains things.

        If you are referring to weak emergence ie patterns of molecules that produce apples then fair enough. But if you are referring to strong emergence then you will have provide some evidence.

        Yes, there are two broad definitions of free will. One is totally incoherent and the other one allows people to take their eye off the ball.

        1. In some ways, emergent is not sufficient to explain things by itself. I’ll admit to being unsure of the difference between weak and strong emergence. I re-read the definition from time to time but it doesn’t stick.

          I mostly use “emergent” here as a shorthand to describe separate levels of concern. Being a software engineer, I find the example of a software algorithm (eg, sorting a an array of strings) being able to run on multiple kinds of hardware. When I talk about that software, I don’t have to worry about what hardware it is running on. It just never needs to come up in the conversation. However, when I run it the calculation obvious requires the hardware to exist. This example is also interesting in that some questions, such as which sorting algorithm is fastest, does require reference to the hardware. Other questions, such as how many steps a given algorithm takes to sort a specific set of strings, can be answered independently of the hardware.

    1. But this amounts to begging the question. Yes, free will is something OTHER than determinism or randomness. To say that there is no third option in existence is to simply assume that free will does not exist.

    1. An interesting article. I agree that the computer simulations don’t get near showing ‘agency’. But I think that the author’s comment that ‘simple physical principles, rather than cognitive complexity, can suffice to generate complex, goal-directed behaviour’ is worth thinking about.

      FWIW, Richard Carrier has recently posted a lengthy article on free will on his blog: https://www.richardcarrier.info/archives/17340 Bottom line: he’s a Dennettian.

      1. I’m finally getting to read this. Thanks for the link. I’m about halfway through but I like what I’ve heard so far. Not so much new ideas but a better way of presenting them.

  4. Although I don’t actually believe it, I propose the theory of pan-freewillism. Atoms may not be conscious, but they can have free will. Consider the humble electron. It can choose to spin up or spin down when we measure it with a Stern-Gerlich magnet. Not only that, there is a theorem by physicists Conway and Kochen that proves if we have free will, electrons must too. In other words, there is a much better case for pan-freewillism than for pan-consciousness. I feel a book coming on.

  5. The more I think about it, the less I find for free will. Are there any suggestions from the readers of this esteemed website for recent literatue on the subject of free will vs determinism? I would appreciate references. Many thanks

    1. From the pro-free will side (or at least free-will agnostic), I recommend the 2009
      from Noam Chomsky “Mysteries of Nature: How Deeply Hidden”. Chomsky basically calls for skepticism about a priori claims that matter can’t have this or that property (e.g. consciousness, free will), and brings attention to the historical record of such moves in the time of Newton. Pre-Newton, philosophers were convinced that matter must obey principles of contact mechanics and nothing else. That program failed spectacularly when gravitation was accepted as a non-mechanical property of matter. This episode resulted in a demotion of the goals of science, so that we can only ever hope to understand theories of the world, but not the phenomena themselves. That is, humans are not blank slates with regard to which phenomena can come under their understanding via scientific work: levers and pulleys are fine and dandy, but the phenomena of modern physics have an occult character, much like free will and consciousness. The lesson here is to simply accept that matter can have fantastical properties.

  6. I wish people would stop using the word “illusion” when they only mean “mistake”. If Grandma thinks that arthritis is a bacterial infection, and actually she has no bacterial infection, that doesn’t mean that her arthritis is illusory.

    Someone might think that “solid” means “has particles everywhere between its outermost boundaries” – but that’s just a mistake, not an illusion. It’s doesn’t necessarily matter if 80% of people make the mistake. There’s still a real difference between a solid and a gas.

    Similarly when most people think that all events covered by deterministic natural laws are linked by asymmetric cause-and-effect, this leads them to certain false beliefs about how choices work. But that’s a mistake, and it’s a mistake about physics, first and foremost, and only secondarily about free will. At the most detailed microscopic level, the laws of physics work in both time-directions. If you define “causality” as asymmetric (if A causes B then B does not cause A) then there is no causality at that micro-level. As Sean Carroll explains here.

    All four of Dowd’s candidate definitions of free will are based on making the above mistake. (It would take several essays to explain how.) A better definition would be “up to you”. It turns out that physics makes more things up to you than you might think.

    1. Well put. I also don’t like the use of that word in this context and when applied to consciousness. “Things aren’t what they seem” is a much better description of the situation here than “illusion”.

    2. Agreed, I get frustrated with the way “illusion” is used in the free will debate for similar reasons. It tends to have a “throwing the baby out with the bathwater” effect.

      “Someone might think that “solid” means “has particles everywhere between its outermost boundaries” – but that’s just a mistake, not an illusion. It’s doesn’t necessarily matter if 80% of people make the mistake. There’s still a real difference between a solid and a gas.”

      Yet even then people are often not entirely “mistaken” in referring to things being “solid.”

      If you look up the definition of “solid” you’ll see it all still makes sense of what that term has always been used to describe of the nature of objects of our everyday experience. (If my Easter egg is “solid chocolate” it does indeed have chocolate all the way through rather than being hollow – that’s still true, not an illusion or a mistake, because we aren’t referring to the levels of physics we can’t even see).
      My door is solid – I can’t walk through it like I could a gas or liquid. My wall is painted a solid blue. I can walk on top of the local lake when the water is frozen solid, but not when it’s entirely liquid. Etc.

      So “solid” accurately describes the usual every day true differences between solid things and non-solid things – solid colors, solid objects, difference between air, gas, liquids, etc.

      This is why saying “solid” is only an illusion is not just confusing but wrong, or at least easily causing misunderstanding.
      Even though some aspect of “solid” may be illusory or mistaken, the bulk of what the word actually refers to is real. Physics just refines our understanding of “solid,” it doesn’t remove it or make it illusory. That’s why even after discovering the physics involved, science retained the concepts of “solid, liquid, gas” because they have the MACRO effects that we observe and describe with those terms.

      And I’d say the same goes for ideas like “choice” “agency” “free will” etc in the free will debate.

      That there is *some* amount of illusion or mistakes involved doesn’t entail that the important aspects those words describe don’t exist. Like “solid,” a “better” understanding shows they are not threatened when you understand the physics, but are better understood.

      1. Solidity is an emergent property. It’s a concept that makes sense at a certain level and in a certain context. It’s not a mistake when used in the appropriate context. If someone declared a certain chocolate bunny to be solid, it would be wrong to accuse them of making a mistake or that solidity is a myth because of fundamental physics. IMHO, free will is like solidity. It is meaningful at the human behavior and interaction level. Simultaneously, fundamental physics and determinism can be acknowledged but they play no role in discussions involving free will, of that kind anyway.

  7. The fragment, “we could not have done other than what we did at any moment in time. And, except for the action of any quantum events, the future is completely determined by the past” makes little sense to me. Because of quantum events, the future is not determined and we could have done otherwise (if some quantum event had a different outcome).

    Of course, I am not saying that this is an argument in favor of free will. It is not. However, one should not use determinism (which is not true) to argue against free will. Instead of saying that free will is the view that “we could have done other than what we did at any moment in time” (which we could), one should say that it is the view that “we could have done other than the law of physics, as we understand them now, dictate.”

    1. You clearly haven’t read the large amount of stuff I’ve written about free will on this site. I’ve said that the future is not determined IF quantum events play a macroscopic role in the future, which they probably do even for evolution, vis-a-vis mutation. And “could have done otherwise” is short hand for “made a conscious decision to do otherwise”, which has nothing to do with quantum events, even if they do affect behavior. What you’re saying is what I’ve already specified, and I include quantum indeterminacy in the “laws of physics”

  8. Is a reflex action free will?
    Does It make it free will when you have time to ponder and decide on choices or a particular action?
    If so, it seems time also plays a role in the free will illusion.
    In quantum mechanics time is a ponderance from what I can gather. Is it fundamental or an emergent property of reality.
    Then again… is that a hole in my head with stuff dribbling out.

    1. I think a reflex action is not free will. However, we can consciously suppress a reflex and that is presumably a freely willed decision. I think this is why many think that free will is associated with consciousness. A decision made unconsciously is not considered and, therefore, free will is moot. Yet another example showing that free will is a concept that only makes sense when considered at a human behavioral point of view. In a sense, it isn’t about the action itself but how you made the decision to take the action.

  9. O’Dowd seems hung up on predictability as an important part of free will.

    I would say that most physicists are uninterested in the philosophical issue, so we generally raise the point that it can’t be tested in physics. (A different question than if brain-body reactions are planned before we are conscious about them.) Which inevitably leads to what philosophers want to call “compatibilism”.

    “Free will” is often a technical requirement in quantum physics.

    In the 1980s, John Bell discussed superdeterminism in a BBC interview:[3][4]

    There is a way to escape the inference of superluminal speeds and spooky action at a distance. But it involves absolute determinism in the universe, the complete absence of free will. Suppose the world is super-deterministic, with not just inanimate nature running on behind-the-scenes clockwork, but with our behavior, including our belief that we are free to choose to do one experiment rather than another, absolutely predetermined, including the “decision” by the experimenter to carry out one set of measurements rather than another, the difficulty disappears. There is no need for a faster than light signal to tell particle A what measurement has been carried out on particle B, because the universe, including particle A, already “knows” what that measurement, and its outcome, will be.

    [ https://en.wikipedia.org/wiki/Superdeterminism ]

    Free choice of detector orientations
    The experiment requires choice of the detectors’ orientations. If this free choice were in some way denied then another loophole might be opened, as the observed correlations could potentially be explained by the limited choices of detector orientations. Thus, even if all experimental loopholes are closed, superdeterminism may allow the construction of a local realist theory that agrees with experiment.

    [ https://en.wikipedia.org/wiki/Loopholes_in_Bell_test_experiments#Free_choice_of_detector_orientations ]

    1. So the only two respectable physicalist options that remain in the modern day are either superdeterminism (which abolishes the determinist’s notion of human behavior as due to a panoply of weakly-determining causes) or pan-libertarianism (particles endowed with free will, as per Conway and Kochen’s Free Will Theorem)? Am I correct in thinking that?

  10. Consciousness is an emergent phenomenon, but not freedom. Consciousness allows the external world to impact the atoms inside a skull in a novel way. When you read an idea on a website, that idea changes your brain. But ideas are completely deterministic too, and, like consciousness, completely dependent on the laws of physics. I have no idea why some people think that freedom can “emerge”, it can’t, it’s not a conceivable thing.

  11. Libertarian free will is also an underpinning of the Indian karma-based religions, Hinduism, Jainism, and Buddhism.

  12. I can’t comment in the Spacetime free will episode, but I will vouch for the channel’s episodes on forefront physics and cosmology, and its treatment of basic physical principles. They are superb.

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