In a recent podcast neurosurgeon Michael Egnor talked with Robert J. Marks about the mind and its relationship to the brain and about different theories as to how the mind works. One of the theories they discussed was eliminative materialism, the idea that there is no mind, really; it’s just the brain buzzing.

Here is a partial transcript with some notes:

01:55 | What defines a good theory of the mind?

Robert J. Marks (right): What constitutes a good theory of the mind and the way the mind relates to the body and the brain?

Michael Egnor: Well, it’s a great question and a very important question. It was actually a question that Aristotle. (384–322 B.C.E.) asked. In his work De Anima, he asked, what would a good explanation for the soul consist of?

Robert J. Marks: You mentioned the idea of a “soul.” Is this the “mind,” according to Aristotle?

Michael Egnor: Yes. What we call the mind is more of a subset of what the classical philosophers called “the soul.” They saw the soul as that which makes a living body alive—what we would call the mind but also the physiological functions, the heartbeat, and all the physiology that goes along with it. And actually, I think that’s a more sensible and comprehensive view of the human being. So what we think of as the mind is just several of the powers of the soul.

[Aristotle], in other words, didn’t separate what we would call the mind so sharply from what we would call ordinary physiology, breathing, heartbeat, and the like. He thought of it all as an integrated whole.

Robert J. Marks: I see. So could you be more specific about what constitutes a good theory of the mind and the way the mind relates to the body?

Michael Egnor: Well, the very first thing we need is a theory that makes sense. And by that, I mean at least a theory that is not internally self-refuting. A good example of a self-refuting theory of the mind is eliminative materialism. [ … ] It is the viewpoint that the only thing that exists is the brain. There is no mind, that what we have come to think of as our mind is just the physical processes going on inside our brain.

03:51 | The self-refuting theory of eliminative materialism

Eliminative materialism (or eliminativism) is the radical claim that our ordinary, common-sense understanding of the mind is deeply wrong and that some or all of the mental states posited by common-sense do not actually exist and have no role to play in a mature science of the mind.

William Ramsey, “Eliminative Materialism” at Stanford Encyclopedia of Philosophy

That is different from another theory of the mind called identity theory that was held in the twentieth century but has been pretty much discarded:

Identity theory is a family of views on the relationship between mind and body. Type Identity theories hold that at least some types (or kinds, or classes) of mental states are, as a matter of contingent fact, literally identical with some types (or kinds, or classes) of brain states. The earliest advocates of Type Identity—U.T. Place, Herbert Feigl, and J.J.C. Smart, respectively—each proposed their own version of the theory in the late 1950s to early 60s. But it was not until David Armstrong made the radical claim that all mental states (including intentional ones) are identical with physical states, that philosophers of mind divided themselves into camps over the issue.

Steven Schneider, “Identity Theory” at Internet Encyclopedia of Philosophy

It’s been discarded because it’s logical nonsense. Every attribute of the mind, reason, emotion, perception, all of those things are completely different from matter, That is, one describes matter as extensions in space; one describes perceptions and reason and emotions in completely different ways. There’s no overlap between them so mental states can’t be the same thing as physical states. They actually don’t share any properties in common. They’re clearly related to one another in important ways but they’re not the same thing.

Eliminative materialists go one step further. They actually say that there are no mental states, that there is only the brain. Which is kind of an odd thing to say because what eliminative materialists are saying is that their ideas are mindless.

How can you have a proposition that the mind doesn’t exist? That means propositions don’t exist and that means that you don’t have a proposition.

Robert J. Marks: So that’s the self-refuting you were talking about…

Michael Egnor (above left): Yes, it’s crazy, and Aristotle made that point: The very first thing, if you are going to explain the soul (or the mind), is that what you say has to make sense.

There’s a neuroscientist named Bennett and a philosopher named Hacker who have written extensively on this and topic of neurophilosophy and have written some very good things. And their motto is that the precondition of truth is sense. That is, that you can’t pretend to have a scientific truth or a philosophical truth or any kind of truth if the statement that you are making about it doesn’t even make sense. Eliminative materialism is self-refuting: If it’s true, then it’s false.

Note: M.R. (Max) Bennett and P.M.S. (Peter) Hacker are the authors of Philosophical Foundations of Neuroscience (Wiley-Blackwell, 2003):

In this provocative work, a distinguished philosopher and a leading neuroscientist outline the conceptual problems at the heart of cognitive neuroscience. Writing from a scientifically and philosophically informed perspective, the authors provide a critical overview of the conceptual difficulties encountered in many current neuroscientific and psychological theories, including those of Blakemore, Crick, Damasio, Edelman, Gazzaniga, Kandel, Kosslyn, LeDoux, Penrose and Weiskrantz. They propose that conceptual confusions about how the brain relates to the mind affect the intelligibility of research carried out by neuroscientists, in terms of the questions they choose to address, the description and interpretation of results and the conclusions they draw. The book forms both a critique of the practice of cognitive neuroscience and a conceptual handbook for students and researchers.

– Editorial Review

So the first thing is that your theory has to make sense. And I think there are various theories that do make sense in varying degrees.

The second criterion is that the theory needs to offer a reasonably good explanation for the mind and for the body and it has to fit the evidence. And you very much want the theory to be consistent with the results of neuroscience obviously. Neuroscience is a beautiful and powerful field. Neuroscience has, I think, been philosophically misguided in substantial ways but we have to take the experimental evidence, the data, quite seriously and try to understand it in a way that makes sense.

Next: Why the mind cannot just emerge from the brain

Show Notes

Is the mind an emergent property of the brain? Or is there something else going on? Robert J. Marks discusses the different theories of the mind — including materialism, panpsychism, and dualism — with Dr. Michael Egnor.

00:37 | Introducing Dr. Michael Egnor, Professor of Neurosurgery and Pediatrics at State University of New York, Stony Brook
01:32 | We can use our minds to understand our minds
01:55 | What defines a good theory of the mind?
02:26 | The mind vs. the soul
03:51 | The self-refuting theory of eliminative materialism
07:12 | A reasonably good explanation that fits the facts
08:09 | What theories of the mind make sense?
08:32 | A materialist perspective of the mind
10:04 | The idea of emergence
11:26 | The wetness of water
13:27 | Qualia — the way things feel
14:17 | Two problems of explaining consciousness
15:40 | Panpsychism
17:49 | Dualist theories of the mind
18:29 | Cartesian dualism
20:00 | Hylomorphism
21:17 | Comparing theories of the mind
25:32 | The emerging field of neuroscience and its effect on theories of the mind

Further reading on theories of mind:

Can we engineer consciousness in a robot? One neuroscientist thinks we need only “simple guidelines.” His underlying assumptions are just wrong.

and

Neuroscientist Michael Graziano should meet the p-zombie (Michael Egnor) To understand consciousness, we need to establish what it is not before we create any more new theories.