The Computational Universe

When I was reading Searle’s article, especially his discussion about the distinction between syntax and semantics, I found myself thinking of a famous thought experiment from philosophy of mind. In debating qualia or the qualitative aspects of consciousness (akin to what Searle calls semantics) philosophers have proposed the following scenario:

Imagine a woman named Mary is in a room and she has had an operation where she can only see in black and white. She has access to all the cutting edge medical technologies and research and becomes the world’s foremost expert on color vision. In particular, she knows everything there is to know about seeing the color red (wavelengths, rods, cones, etc). No matter how much she knows, however, we have an intuition at least that if the procedure is reversed and she is taken outside the room and sees something red, then she will learn something new namely what it MEANS to see the color red or what red looks like.

Some argue that Mary will not learn anything new when she first sees red in which case artificial consciousness seems plausible. However, if she does learn something new then there seems to be something about qualia intimately bound up in consciousness which does not bode well for AI. I am not sure if this connection I am drawing is exactly correct, but it is what I found myself thinking when I was reading Searle’s article.

One of Professor Arora’s lecture slides also brought up an interesting point: surely we would all concede that human consciousness is a strong form of consciousness. There are other life forms that we would admit to be conscious, but in a much weaker sense. Could then computers become conscious in some weaker sense? I think this has to seem much more plausible than a computer passing the Turing Test. However, the difficulty becomes how would we test if a computer has become conscious in this weaker sense? Could the Turing Test be extended to say that if humans and some examples of whatever given animal cannot tell the difference between that animal and a computer, then a computer has attained that level of consciousness? On an intuitive level this seems wrong (it is no stretch to imagine a robot that might fool a dog into thinking it is a dog, and because humans are not well acquainted with the consciousness of dogs, also fool a human as well), yet it is hard to think of a better analogous test to the Turing Test.

Anyways, sorry to ramble, just thought I would share some of those reactions to Searle’s article and our larger AI discussion which I have really enjoyed.

Tim Berners-Lee’s lecture about the future of the Web, while interesting, was definitely one which I wished I had had an opportunity to do some background reading on before attending. Others have already commented on the opacity of his technical discussion of the Semantic Web. I definitely agree with them. However, there was still a lot that I took away from the talk. I thought he gave a very nice explanation of the added value of the world wide web when he said that the hope is that you post some useful information which someone you don’t know and may never meet will read and put to a use you never could have imagined. Of course, this is a rose-tinted vision of the world wide web, but as a sort of ideal I think it is a good one.
Another seemingly minor point I found interesting was his discussion of email from the perspective of technical and social rules. At first, email was used among the academic community with the understood social regulations that you would only send emails when it would be to the mutual benefit of sender and recipient. As personal email accounts proliferated, commercial interests began to encroach on the idyllic state email once enjoyed and “spam” began to become a problem. It seemed Sir Berners-Lee had a very dismal outlook for the future of email absent some change in the “incentive structure” as he called it. I also found it funny that a degree in physics used to be called a degree in “experimental philosophy” which now seems something like an oxymoron.

As a philosophy major, what first caught my attention about Turing machines or Turing-Post programs was that they were conceived as a response to what was once considered a philosophical question first posed by Leibniz. That computation can be reduced to a mechanical process accomplished by a linear tape, a scanner, and seven commands seems even now a counter-intuitive proposition to someone unfamiliar with computer science—all the more so when you realize that these commands can form programs that can be represented by strings of 1’s and 0’s but which themselves can also become inputs. I think I learned the most when the material seemed most foreign to me. For instance, I felt my lack of a computer science background most acutely when trying to grasp the full import of things like the halting problem. Professor Arora’s example of representing a reductio-type proof through the interactions of two programs helped me get my mind around the power of Turing machines to show the theoretical limits of computation.
Another thing which surprised me about Turing machines, and I am still not sure I 100% grasp, is the concept that there exists a universal Turing machine capable of performing every possible computation. I understand that this program would be capable of separating programs from inputs and then running the instructions of those programs on the inputs. I think what I do not grasp is the more fundamental point that any possible computation can be accomplished by Turing’s 7 commands.

There have been some articles in the New York Times recently that I thought might interest some people as they have to do with some of the stuff we have been talking about in class:

Here is one on the pros and cons of using network theory to catch terrorists:

http://www.nytimes.com/2006/03/12/magazine/312wwln_essay.html?_r=1&oref=slogin

And here is one about robots:

http://www.nytimes.com/2006/03/16/technology/circuits/16robot.html

Hope everyone enjoys their break.

The title of this post comes from a Wordsworth poem which I think is in general very relevant for us seniors in the class, but all the more relevant for me because of its emphasis on LATENESS. There is a line in the poem that goes “getting and spending we lay waste to our powers”–I think any senior trying to balance writing a thesis with worrying about the future/finding a job, classes extracurriculars, and not having a miserable senior spring can appreciate that line. I am sure I am the last person in the class to be completing Lab 1 and I would like to apologize to everyone for the tardiness. I just switched into this class last week and hope to get entirely caught up by next week.

I am a senior in the Philosophy Department from Morristown, NJ (45 minutes north of Princeton). I was excited but not surprised to see that there are a fair number of other philosophy majors enrolled in this course. On campus, I do a lot of creative writing (CRW classes and campus publications), have served on the Priorities Committee, and am a member and officer of Ivy.

What attracted me to COS 116 and ultimately convinced me to drop a much drier class was the way it seemed the course would put a philosophic gloss on computer science questions in a way that was accessible to those of us who feel more comfortable with Nietzsche and Kant than with HTML and C++. I am interested in the space where Computer Science and Philosophy overlap, and from the lectures so far, questions about the limits of computing.

Again, I am sorry for the lateness of this post. Looking forward to getting caught up.

Update 9:44PM on 3/6/06: My computer is an Mac iBook G4…I am basically a sucker for Apple’s whole aesthetic.