Tuesday, August 7, 2018

The mystery of the flame



Colin McGinn is a British philosopher who specializes in the question of consciousness. He is also a great fan of science fiction, which occasionally shines through even in his philosophical writings. In "The Mysterious Flame", he mentions space aliens on every other page, and turns out to have a bad crush on the Star Trek character Seven of Nine (Colin, really!). In another text, he is kidnapped by aliens who turn out to be Platonists!

"The Mysterious Flame" is a popularized and surprisingly easy read. I say surprisingly easy, since philosophy texts on the question of consciousness are often extremely technical, difficult and down-right boring. This is the only exception I've seen so far. The New York Times probably had a point when they said that McGinn's text is the best introduction to the problem of consciousness. Yet, it should be noted that the book isn't neutral. It's fiercely partisan towards McGinn's own perspective on the matter. In many ways, his views resemble those of John Searle. The major difference is that McGinn doesn't believe the question of consciousness will ever be conclusively solved. He therefore calls his position "mysterian".

What makes consciousness such a vexing issue is obvious: thoughts and feelings aren't material objects. They have no extension in space, and can't be pinpointed to a specific location. Also, they are intensely subjective. You can't probe somebody else's consciousness (or know how it feels to be a bat). Despite its non-material character, consciousness is nevertheless connected to a material object: the brain. How is this even possible? How can a lump of material tissue give rise to non-material thoughts, feelings and meanings? This is the mind-body problem, also known as "the hard problem".

McGinn rejects the two standard answers to the problem: materialism and dualism. "Materialism" as defined by McGinn is a reductionist form of materialism, which attempts to show that consciousness really isn't non-material. The mental is identical to the material. Thoughts and feelings are brain states. That they feel non-material is an illusion. Dualism takes the opposite tack: the mental and the material look so different, because they *are* different. The mental comes from another dimension of reality, and isn't necessarily connected to the brain at all. Dualism is most common in religious forms, and connected to ideas about humans having an immortal soul that leaves the body at death, but one can imagine a purely secular form of dualism as well. McGinn spends several chapters debating dualism and other seemingly outlandish philosophies (panpsychism, "total mentalism"), while his discussion of reductionist materialism is very brief. Somehow, McGinn seems fascinated by the notion that the mental, or consciousness itself, is independent of our physical existence. In the end, however, he rejects it together with reductionism.

McGinn's preferred position is that consciousness is rooted in the brain, and that our thoughts, feelings and desires are caused by material processes in the brain. Consciousness cannot be reduced to brain states in the sense of being identical with them, but it nevertheless emerges from brain states. (I always considered this to be a trivial position, but apparently it's controversial among philosophers!) However, McGinn also believes that we will never know exactly how the brain produces consciousness. Our minds aren't properly equipped to grasp their own inner nature. Consciousness is of necessity first person: we can see other people's brains, but we can't see other people's consciousness. Conversely, we can introspectively probe our own consciousness, but nothing in it tells us what material process gave rise to it. We are, in McGinn's phrase, cognitively closed.

McGinn further argues that we can't even know everything there is to know about our own consciousness. Not even introspection will reveal its deep structure, the essence of our own minds. We can't even explain what it means to have a self! And since we can't do this, we will never be able to guess what biological processes gave rise to consciousness.

The main problem with McGinn's position is, of course, that if we can't know the cause of the mind, the cause might very well be materialist or even dualist! How are we to tell? Dualism in its strong form cannot explain why mind and matter are correlated at all. In its weaker form, however, dualism is more difficult to argue against. A "weak" dualist could argue that a brain is necessary to create consciousness by bringing together material and mental elements. This would explain the correlation between mind and matter in the brain, while still considering them to be fundamentally different properties of the world. The argument against such a dualism would simply be that it doesn't really explain anything, since we still don't know *how* the brain makes consciousness out of mental and material properties. But then, dualism and "mysterianism" are equally mysterian! McGinn's main argument against dualism is that mental and material states in the brain are just too perfectly correlated. Dualism in any form is therefore unlikely. But if we are cognitively closed, how can we know for sure? There is a certain tension in the book between "mysterianism" (which should be strictly agnostic) and the emergent materialism I take is McGinn's "real" position.

McGinn also discusses whether robots can be conscious. He reaches the conclusion that they cannot be. Consciousness isn't simply a computer program. A computational program can only simulate intelligence. Actually, it's unintelligent. A robot who speaks Italian just because its been programmed that way, doesn't really understand Italian. (Think of a parrot that mimics human speech!) It's a mindless zombie, even if it says all the right things. For a robot to be really conscious, it would have to have a brain with the right properties for consciousness, but its precisely these properties we don't know about, and probably never will know about. Besides, whatever property makes us conscious, it's probably organic. Consciousness arising from a metallic brain is, while not intrinsically impossible, at least highly improbable.

"The Mysterious Flame" might strike readers new to the subject as defeatist. Shouldn't scientists and philosophers attempt to find a solution to these and other problems? Shouldn't we, to quote Star Trek, boldly go where no man (or Andorian) has ever gone before? Such people might be surprised to hear that philosophy at least since the time of Hume and Kant, have been as much preoccupied with telling us what we *can't* know. Knowing the limits of our knowledge might, after all, do us some good!

And if Colin McGinn is right, we will never solve the problem of the mysterious flame...

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