virus: Penrose Is A Genius

David Leeper (
Tue, 28 Aug 1956 02:10:47 +0000


I just finished reading Roger Penrose's book "The Emperor's New
Mind" and I must say it was quite impressive. Penrose tackles
the question of whether or not computers will ever be able to
have the functionality of the human mind. In contrast to most
experts, Penrose says "No".

While I personally disagree with this answer, his arguments were
devistating in their precission and quality. The scope of these
arguments, ranging from computer theory, to quantum mechanics, to
neurology, was truly impressive. I think it's fair to say that
only a few people in the history of mankind could have written
a book like this.

Definitely worth the read for anyone struggling with questions
such as "Who are we", "Free Will vs. Determinism", and so on.
Published by Penguin Books.

* From the chapter "Alogorithms and Turing machines".
Penrose describes Turing machines and, using Godel's Theorm,
shows that there are statements the human mind can see as true,
but which Turing machines can't.

* As all computer programs are examples of a Turing machine,
this means that _all_ computer programs will suffer from this
* Techniques for writing computer programs which use evolution,
such as genetic algorithms, do not escape this problem. Each
evolved program is still a Turing machine.
* Techniques for running computer programs in parallel, often
claimed to hold much hope in this area, do not escape this
problem. A Turing machine run in parallel is still a Turing
* From the chapter "Real brains and model brains".
Penrose describes split-brain experiments where when the left
hemisphere of the brain is split from the right hemisphere of
the brain, two (!) personalities actually arise within the brain.

* Such experiments deal a hash blow to those hoping to point to
a spot in the brain and say "There lies consciousness.".
* Such arguments deal the same blow to those wishing to model
this or that part of the brain on a computer, in hopes of mimicing
* From the chapter "In search of quantum gravity".
Penrose details why he believe current quantum theory is a temporary
theory which will have to be replaced.

* This new theory will replace both the deterministic and probabilistic
parts of current quantum theory.
* This new theory, says Penrose, will be time-asymmetric, unlike nearly
all of existing laws of physics, yet much like the brain.
* This new theory, says Penrose, have a good chance of explaining the
actions of the brain as it displays both algorithmic and non-algorithmic
That's enough for now. I think I've made my point. For those of us
interested in the area of artificial life, Penrose's book outlines
several roads which would seem to turn into dead ends.

So why do I ultimately disagree with Penrose's "No" despite the fact
it's supported by such excellent arguments? The answer is that my own
beliefs lie down other roads; near but not identical to those discussed
by Penrose.

For example, rather than thinking that this or that spot in the brain
holds the seat to consciousness, I've always believed that consciousness
emerges from the complex interactions brain, body and environment. If
anything, Penrose's discussion of split-brains actually provides some
support for this idea. Similarly, I don't believe awareness will _every_
be found in this or that alogorithm, but rather will emerge from the
complex interactions of many alogoritms interacting.

David Leeper
Homo Deus  
1 + 1 != 2