Yesterday I deconstructed Michael Egnor’s tangle of logical fallacies and false premises that he uses to attack modern neuroscience. There was one point I forgot to address, however. (One of the hazards of daily blogging.) It’s important enough to warrant a separate entry, however.

Reader Gary Goldwater hit upon this contradiction, although tangentially, with this comment:

I also wonder to myself….and perhaps you can explain this…how a brain surgeon would come to Egnor’s conclusions. If my knowledge base is correct, a brain surgeon would have a professional lifetime experiencing the direct connection between the material brain and the function of mind. It seems to me that one of the major foci of a brain surgeon is to limit collateral damage during surgery for the specific purpose of limiting an affectation in the patient’s mind.

The answer to Gary’s question lies, I think, in Egnor’s logical contradiction I did not point out yesterday.

Egnor’s position is that the mind is not caused “entirely” by the brain. He asks in his recent essay, for example,

So is the materialist inference that the mind is caused entirely by the brain plausible?

Egnor is employing a common denialist strategy – finding a way to accommodate undeniable scientific evidence while denying its implications. This is the exact logical equivalent to the “microevolution” tactic of creationists. Essentially, any slam-dunk evidence that evolution is actually happening in the living world is only evidence for “microevolution,” and does not prove “macroevolution.” It also equates to the creationist denial of a pattern of common descent in genes and fossils. “So there was a dinosaur-looking feathered creature that flew. That doesn’t mean it was actually a transitional form from dinosaurs to birds. It just was what it was.”

Egnor acknowledges the mountain of evidence that mental activity correlates with brain function. He can even practice neurosurgery based upon our extensive knowledge of what brain bits perform which mental functions. But he does two things: He denies that the correlation is exact, essentially relying upon current technological limits in our ability to image brain function. And he denies the obvious implications of the strong correlation that can be documented scientifically.

He tries to rescue his position, which he knows it at odds with the evidence from neuroscience, by saying that the brain does not “entirely” cause the mind. This still leaves him the out of saying that there must be some magical non-materialist cause also. He only needs the tiniest bit, the smallest sliver of uncertainty, to claim victory over materialism. This is an obvious attempt to insulate his position from scientific evidence about brain function.

But he creates another problem for himself, which came to a head in his recent post. He argues (falsely) that there are six features of mind that cannot be explained at all by a materialist model of mind. He essentially argues that matter can have no relationship with these phenomena – such as qualia or intention.

But then – how does the brain partly cause the mind if all the really important stuff cannot be caused by brain matter at all? And, why would brain function correlate at all with the mental functions he discusses?

If, as he claims, the continuity of our personality is independent of the organization of matter in our brains – then how come personality can be radically and immediately changed by damage to the physical structure of the brain? How can frontal lobe damage cause someone to become apathetic or disinhibited, for example?

Egnor’s position is ultimately incoherent and self-contradictory. He is using the “kettle defense” strategy – making any argument he can for his position, even when they are mutually exclusive.

He is forced into incoherence, however, because his position is ideological and untenable. Mental function correlates with brain function in every way, within our technical limits to measure such things.  Brain maturity correlates with mental maturity. Drugs that change brain function change mental function. If you damage the brain you damage the mind. When our brain’s sleep we sleep, and when we dream our brains are dreaming. Remove a part of the brain and the mental function that correlates with that piece of brain goes with it. The severity of dementia correlates with the extent of atrophy and pathological changes in the brain.

And (here is perhaps the real sticking point) when our brains finally die, we die. There is no credible evidence for any persistence of self beyond the ongoing activity of our brains. People can retain whatever personal faith they wish, but within the realm of science, when brain function ends, mental function ends with it.

None of this would be true, however, if Egnor’s six points were valid, and he cannot rescue this contradiction by saying that the brain “partly” causes mind. If brain causes mind at all, then all six of his arguments must be false.

But Egnor demonstrates one more brain-caused mental function – the ability to compartmentalize; to maintain mutually exclusive beliefs at the same time. As he demonstrates nicely, compartmentalization leads to incoherence.