CeeBod said:
rgrekejin said:
As J.B.S. Haldane once said:
"It seems to me immensely unlikely that mind is a mere by-product of matter. For if my mental processes are determined wholly by the motions of atoms in my brain I have no reason to suppose that my beliefs are true. They may be sound chemically, but that does not make them sound logically. And hence I have no reason for supposing my brain to be composed of atoms."
At the risk of going off on a tangent here, I'd suggest that that J.B.S Haldane quote makes it sound like he's espousing Cartesian dualism which was rather an outdated philosophy even during Haldane's lifetime. We know that a brain is composed of entirely ordinary matter made from entirely ordinary atoms, and it makes more sense to think of mind as being a process of the brain, much like life is a process of the body:Any emergent process can be orders of magnitude more complex than the physical matter that spawned that emergent process. Invoking something mystical and immaterial to account for this, like for example a soul, is just bad science.
I don't know in what context Haldane's quote is from, but he's a respected enough scientist that I'd be surprised if that inference was where he was going with his line of reasoning.
Some form of dualism, as a philosophy of the mind, is still around today, and is a position held by a lot of serious thinkers in the field (disclaimer: I am a hylomorphist, not a Cartesian dualist). I'm not sure what specifically you mean when you're talking about the mind as a process of the brain, but I think that Rosenberg, in the book I refer to above, makes a good case that any consistent materialism *must* take an eliminative position a la Dan Dennett towards the mind, rather than a reductionist position (some thinkers, notably the Churchlands, dispute this, but I think they're wrong for reasons I won't go it to here). And either position is nonsense anyway - John Searle is the man to read for a demolition of eliminatism and reductionism and a muscular defense of the irreducibility of the mind. If materialism entails eliminatism, and eliminatism fails as an explanation, then materialism is false. Curiously, Searle claims that he himself is not a dualist, but, upon examining his actual position, it seems to me that he's just a dualist who doesn't want to be called a dualist.
As for the fact that the brain is solely composed of atoms - yes, it certainly is, but saying so misses the point. The point is not that the brain is not composed of atoms, but that the mind is not identical to the brain. There is obviously a relation between them, but they are not ontologically identical. Haldane, frankly, could have phrased that better at the end, something like "I therefore have no reason for supposing my mind to be composed of atoms." And his basic point stands - if thoughts are determined solely by chemical functions in our skull, how can we possibly know them to be true or false, logically valid or not? The fact that truth exists, that the laws of logic work, and that intentionality is real, cannot have a purely material explanation, at least not as matter is presently understood. Haldane knew this - he may have been a well respected scientist, but he had a very firm grip on the limits of what science was capable of telling us, certainly better than the philisophical philistines running around today (we're looking at you, Lawrence Krauss). Evidence of this is seen in a number of his famous quotes:
"Teleology is like a mistress to a biologist: he cannot live without her but he's unwilling to be seen with her in public."
"My own suspicion is that the universe is not only queerer than we suppose, but queerer than we *can* suppose."