This book took far longer to finish than it should have. This is in large part due to the silly conclusion Penrose tries to reach, which just makes my brain bleed.
The thesis of the book is simply this:
- Consciousness is not deterministic, therefore the brain works
It starts promisingly enough, with an explanation of Turing machines, computability, and the Turing test. Having explained these concepts, Penrose then tries to argue that the brain is, in fact, not a deterministic Turing machine.
Central to this claim seem to be the Chinese Room experiment and similar thought experiments (which I’ll grant can be difficult to grasp properly), and various minor things like “flashes of insight” (which clearly can’t be explained deterministically!) and whatnot.
Fortunately, he quickly abandons this line of reasoning and starts talking about mathematics and quantum physics for a few hundred pages. I’m not sure why he does this, since neither has any relevance to the subject at hand, but I’m not complaining.
He tries to return to the brain in the final chapters, but he just makes an ass of himself in the process.
Penrose doesn’t understand psychology, physiology, fetal development, evolution or natural selection (at some points coming perilously close to endorsing ID), the (often counter-intuitive) capabilities of actual computers, or cognitive science, but he tries to venture into each of these fields to make his point and fails spectacularly.
His whole point is essentially a giant, infuriatingly dense argument from incredulity and personal pride (the human brain can’t be a deterministic Turing machine, that would make it too common!), and his attempts to involve quantum physics are more reminiscent of Deepak fucking Chopra than of a theoretical physicist of Penrose’s stature.
Now, does this make The Emperor’s New Mind a bad book? Well, yes. Let me rephrase.
Does this mean The Emperor’s New Mind isn’t worth reading? Absolutely not.
Like I said, most of the book is just seemingly irrelevant stuff about mathematics and quantum physics, and it really is quite interesting. It’s worth keeping in mind that Penrose isn’t just some random woo artist, but an accomplished mathematician and actually a rather competent theoretical physicist.
He talks about Turing, fractals (including the Mandelbrot set), Penrose tilings, the history of physics, and plenty of fascinating concepts in theoretical physics ranging from well-known to rather obscure. If you’re willing to gloss over his forays into cognitive science and AI, and maybe skip the last chapter entirely, it’s actually a very good read.
As far as philosophy of the mind goes, though, I’d just leave that to people like Daniel Dennett.