Steven Pinker’s take on the material mind

February 15, 2009 • 9:37 am

I sent Simon Conway Morris’s attack on the Darwinian evolution of human mind and consciousness to my colleague Steven Pinker at Harvard (for those of you who have been in Ulan Bator for the last two decades, he’s an eminent psychologist and linguist who has written extensively on the mind, language, and evolution).  Steve had a thoughtful response, which he kindly gave me permission to post here:

My own take:

1. Though there’s much we don’t understand about the evolution of human intelligence, nothing about it is especially mysterious. A specific ability to do physics, abstract philosophy, higher math, and the other problems that vexed Wallace never evolved in the first place – they require millennia of accumulated knowledge in a culture, and decades of education and honing in an individual. A more generic ability entertain concepts of number, objects, living things, causality, and so on, and to combine them into lawful generalizations, is patently adaptive, as we see in the ways that all human cultures depend on acquired technological know-how for their survival, outsmarting the fixed defenses of local flora and fauna. While human-level intelligence is species-specific (as are many zoological traits, such as the elephant’s trunk), impressive levels of numerical cognition and cause-and-effect reasoning have evolved several times, including in corvids, cetaceans, cephalopods, and primates.

2. Nor is morality any mystery. Abstract, universal morality (e.g., a Kantian categorical imperative) never evolved in the first place, but took millennia of debate and cultural experience, and doesn’t characterize the vast majority of humanity. More rudimentary moral sentiments that may have evolved – sympathy, trust, retribution, gratitude, guilt – are stable strategies in cooperation games, and emerge in computer simulations.

3. No feature of consciousness has ever been discovered that does not depend 100% on neurophysiology. Stimulate the brain with chemicals or an electrical current, and the person’s experience changes; let a person’s experience vary, and you can measure the changes in chemistry or electrophysiology. When a brain is damaged, the person’s mental life is diminished accordingly, and when the brain’s activity ceases, the mind goes out of existence – Wallace’s séances notwithstanding, no one has found a way to communicate with the dead. The very existence of a subjective correlate of brain activity may not be understood (if it’s an intellectually coherent problem at all, which some would deny), but positing a “soul” simply renames the problem with no insight, and leaves the perfect correlation between consciousness and neurophysiology unexplained.

18 thoughts on “Steven Pinker’s take on the material mind

  1. That is a nice piece. Thanks for getting his contribution.

    I particularly liked point 3, that no feature of consciousness is disconnected from neurophysiology. This point should allow Conway Morris to argue that, if he was correct, there must be at least some component of consciousness that is generated by the supernatural world. He could predict that there is a feature of consciousness that is not affected by chemicals or electrical currents. Other religious “scientists” could test this hypothesis. However, like most people who construct the fantasy of a personal god they never appear open minding and suggest, for example, that their assertions should be rigorously tested. A test or some good evidence would help everyone’s understanding, most importantly it would advance their own understanding of the world.

  2. Thanks for the post Jerry. Steve Pinker has written a clear and concise takedown of Conway Morris’s ramble.

    The real problem with theist writers is they are actively misleading the reading public. There is deceit behind their words and an agenda other than science and the pursuit of truth.

  3. It’s a good take on it all, though personally I’m baffled that people still try to contend that the mind is not material. Surely the link between physical trauma to the brain and the loss of consciousness is well established.

  4. After I saw this article, that rambling about the mind made me wonder what Steven Pinker would think about CM’s assertions, and here it is, putting it all together in a way that a hick like me can understand.

    Thanks for providing this. 🙂

  5. I wanted to thank you for this, but it seems others have already. So I’ll go one step further and thank you for this blog. Please keep writing it.

  6. no, No, NO! The brain is just a god-designed cage for the conscious soul. When the material mind is damaged, the cage door springs open, allowing the spirit to see through the firmament onto heavenly father’s holy throne!

    *removes jumper cables from temples*

    Pinker was right; electricity does change the functioning of the mind!

  7. Doesn’t Pinker’s point about intelligence arising in corvids, cetaceans, cephalopods, and primates indicate the convergence that Morris was after? I don’t see how it gets what he wants (the inevitability of humans), but in convergence nonetheless.

  8. Nice piece, and some really great writing on this blog as a whole – thank you Jerry! (And Steven.)

    Just one related comment – actually triggered by my reading of “downunder fans” comment. One thing I NEVER understand.

    You get a well-respected biologist/mathematician/chemist/whatever, and they have an experience/an epiphany/a sneaking suspicion that “there’s more to it than what I have been told/am teaching/have researched for the last X years”.

    OK, so your man (interestingly – rarely is it a woman) now has a suspicion that “there’s more to it”. They are turning to “theisty” kind of thinking… wondering what could be “out there” (or “in there”).

    OK, I buy all that. I can understand the attraction – even the intellectual interest in wanting to challenge accepted thinking. Or even – since mortality sucks – wanting to believe it ain’t necessarily so.

    But why the FSM do these guys – in their moment of doubt, their epiphany of theism and soul-searching – go pick an old, dusty religion like Christianity as obviously containing the answer?

    It would be like doubting a modern researcher’s work on, say, blood clotting, and then adopting the theory of the Four Humours as obviously more “logical”.

    Scientist to deist I can understand – scientist to old-time theist I will never fathom.

  9. @downunder fans

    I completely agree. Postulating the existence of soul is equivalent to the assumption that the laws of physics are constantly being violated in our brains.

  10. There are flaws in at least the idea that thinking can be modeled in terms of computational intelligence, etc. Computations work with numbers in effect, and can’t represent anything that isn’t some sort of mathematical structure. Well, as modal realists have explained: the very idea of substantial existence (“real stuff” being distinct from Platonic forms) cannot be coherently defined and explained in strictly logical terms. We not only can’t explain why some possible worlds, have a special trait called “existing” and others don’t, we can’t even explain what the distinction consists of to start with. Hence thinkers like David Lewis said all such worlds “exist” with equal standing.

    Note that the thinking done in a model simulation is just like that in a “real world” – if both are defined in AI terms. Hence, the AI entity can’t even frame the thought, “I am a material being and not just part of a program simulation or Platonic structure of math (as in MUH.) The hilarious irony, is that those who believe in AI concepts of human thought *have to be modal realists* to be honest. They don’t believe in a way to conceive of substantial worlds being distinct from the mathematical process itself. Hence, all such worlds exist and there is no point in “physics” or materialism per se.

    Neither can we logically define “real flowing time” as a special way for reality to be, distinct from simply there being a configuration of points and lines (world-lines) in a “space” of four-dimensions. Yes, we represent time in math, but there is no definition of it as a distinct entity, no mathematical way to point to the “t” in dx/dt and say, “That is some special trait and not in kind like the “x”. Yet somehow our minds grasp or profess these distinctions, as the do the idea of “consciousness” being special.

    Final ironic observation: the crusty old-skeptic notion of a singular, brute-fact of special “material existence” distinct from other “possible worlds” can’t even be made a coherent logical claim.

  11. I am surprised by the lack of comments about Penrose/Hameroff theory of consciousnss being related to quantum states inside brain microtubules. Notwithstanding the fact that said theory could be construed as another try at linking consciousness to the material structure of the brain, I agree with Penrose’s thesis that consciousness canot be reduced to an algorithmical process.
    There are some unexplained phenomena that seem to indicate that consciousness cannot be restricted by the bony cage of our cranium. How could Pinker explain the fact that
    when my wife underwent a temporary cardio-respiratory arrest, lasting 8 minutes, her pet dog exibited signs of acute stress (at a distance of 150 miles, no less!). Or that some persons exhibit a special sensitivity to death of relations, friends, and so on? My daugter’s sister-in-law is such a person and had a vision of my wife at the moment of her death (also 200 miles away).
    Such communications at a distance are not amenable to purely material explanations. Physical “fields” like electromagnetic waves cannot be considered likely (electromagnetic fields decay with the square of the distance). Something else must be happening, and a non-material nature of consciousness cannot be ruled out offhand.
    Let us remember J.B.S.Haldane (a neo-Darwinian and a marxist to boot!): “My own suspicion is that the universe is not only queerer than we suppose, but queerer than we can suppose.”

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