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Reviewed by Robert Ettinger
This book of by M.I.T.'s Artificial Intelligence guru Marvin Minsky (Simon & Schuster) is a couple of years old, and has been reviewed fairly widely (and usually rather favorably). Still, now that I have finally gotten around to it, it may be worth passing on some impressions.
It is entirely nontechnical, without even any references--just a bibliography mingled with a glossary. The author even says it is just a compilation of speculations about the functioning of some aspects of the brain. To anyone looking for enlightenment about consciousness or identity it is totally disappointing. It includes what seem to me to be a few clear-cut mistakes. All this is the downside.
On the upside, it includes a lot stimulating suggestions, mostly stemming from the melding of Minsky's interests of computer math and psychology, with many common-sense insights. Douglas Hofstadter has called it "...a stunning collage of staccato images, filled to the brim with witty insights and telling aphorisms." That's a bit effusive, but not unpardonable.
Let's look first at some of the apparent mistakes, beginning with "Fredkin's Paradox" which the author approvingly notes:
"The more equally attractive two alternatives seem, the harder it can be to choose between them--no matter that, to the same degree, the choice can only matter less."
Balderdash. Admittedly, a fussy diner might hesitate between steak and,lobster,,.but not for too long, and nothing hangs in the balance. In the real world, the choice might be between war and peace, with enormous possible consequences either way; or the voters might have to choose between two political parties, each with its peculiar attractions and repulsions; or a company might have to choose between two takeover suitors, each with something different to offer. What makes the choice hard is that the balance is unclear but a great deal is at stake.
A more important obfuscation occurs more than once in his discussions of consciousness. At one point, he says: "...consciousness is knowing what happens in our minds right at the present time." Elsewhere he says, "...consciousness consists of little more than menu lists that flash, from time to time, on mental screen displays that other systems use."
The difficulty is that he confuses awareness with the content of consciousness. The "display" is the content, and consciousness itself is more than a screen. Perhaps the most important problem in biology is the nature of consciousness and any substrate--what I have called the self-circuit. Consciousness is that aspect of brain which allows the subjective condition--i.e., feeling and observation. On this point Minsky has nothing to say.
A minor but strangely crude error occurs in this passage:
28.8 OVERLAPPING MINDS
Consider the popular idea that a person is capable of two kinds of thinking at once – a right brain kind and a left brain kind – as though there were two different individuals inside each human brain. This raises some odd questions, since there are many other ways to draw imaginary boundaries through brains.
If you agree that each person has a left-brain mind and a right-brain mind, then you must agree that each person also has a front-brain mind and a back-brain mind! Can a single large mind contain so many smaller ones, with overlapping boundaries? It makes sense to think of part of a structure as being a ‘thing’ in its own right only when the relationship among parts of that structure have some significant type of coherency. Before you’d say that a certain arbitrary section of brain contains a mind, you’d want to have some evidence that what happens inside that boundary is something you would consider to be a mind.
The point is that,the lines are not equally imaginary. There is a fairly well defined physical boundary between left and right hemispheres, and animals (including people) can live and function with only one hemisphere of the cortex; this is not true of "front brain" and rear brain. Minsky must certainly be aware of the many split-brain experiments, so this gaffe is puzzling.
The problem of identity is touched upon briefly here and there, but many aspects are omitted and there does not seem to be any real contribution. He seems to feel that a repaired or duplicated mind, meat or metal, would be "you" if the duplication of function is reasonably close. He says, "..the real question is not what we mean by 'you,' but what we mean by 'same’. But this is clearly wrong: we need both questions--otherwise I would have to worry about how closely, for instance, my hair was duplicated and other trivialities.
The good stuff consists primarily of representations of systems and subsystems in the brain, and their interrelationships and schemes of interaction: many tiny automata, acting together in hierarchies, produce an emergent mind.
There are also some shrewd observations on certain stubborn antiscientific misunderstandings. One example concerns the "revelations" people sometimes think they experience--visions of astounding clarity that sweep away all doubt, even though coherent details cannot be produced. This is sometimes the result of "solving" a problem by changing the rules of thought, or pathways in the brain, to banish troublesome doubts and contradictions.
Another is a quotation from W.H. Auden: "We are all here on earth to help others. What I can't figure out is what the others are here for."
Again, he does a splendid job on the myth of "free will" by explaining that (according to modern views) events--including mental events--result either from cause (deterministically, on the classical level) or else by random chance (according to the rules of quantum mechanics) and that neither of these gives any comfort to human dignity. But he does less well in reconciling the basic, lack of free will with human responsibility and dignity.
Another oldie but fairly-goodie is the warning about the danger of self-knowledge: "If we could deliberately seize control of our pleasure systems, we could reproduce the pleasure of success without the need for any actual accomplishment. And that would be the end of everything." This well-worn science fiction theme has some substance, but only some: after all, masturbation has not replaced copulation.
Then there is an interesting speculation about the difference between a feeling of virtue vs. a mere feeling of success. "When we maintain our standards, we feel virtuous rather than merely successful." Plausibly, value systems (as opposed to simple criteria of useful action) are related to the love or rejection of parents.
Finally (since we have to stop somewhere) there is his "investment principle" which tends to explain the obduracy of old ideas vs. new. "Our oldest ideas have unfair advantages over those that come later. The earlier we learn a skill, the more methods we can acquire for using it. Each new idea must then compete against the large mass of skills the old ideas have accumulated." If you can't beat them, try to find some way to join them, or appear to.
Robert C.W. Ettinger
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