Archive for the 'science' category

It’s not what you think.

Feb 06 2010 Published by brian under cognition, science, technology

Today, my spouse and I somehow got into a long discussion of the Chinese Room argument, and I thought I’d share a little here of what I came up with.

If you don’t know, the Chinese Room (proposed by John Searle in 1980, and summarized nicely at the above Wikipedia link) is a thought experiment about artificial-intelligence work, having to do with the level of “understanding” that can be achieved by an AI system. The idea is this:

Imagine a computer that can understand Chinese. It can read Chinese characters, process them, and produce an appropriate response, that can be read by a native Chinese reader and understood well enough that the reader cannot tell the responses from those that would be given by a human fluent in Chinese.

Now imagine that instead of a computer, you have a printout in English of its algorithm, and a human (who does not understand Chinese) who executes the instructions with pen and paper, and produces the same results. Searle’s argument is that functionally, there is no difference between the computer and the human; and, that since the human operator doesn’t understand Chinese, the computer can’t be said to understand Chinese either–and, without “understanding”, the computer can’t be said to be “thinking”.

I won’t rehash the vast range of discussion that we had about this (particularly since I didn’t take notes). But I do have a reply, which is this: the “intelligence”, if there is any, resides in the instructions, not in the person or machine executing those instructions.

Of course, that would seem to put me in the dualist camp–saying that there’s mind and there’s body and never the twain shall meet. But the experiment, to my mind, is missing one detail: the brain is constantly reconfiguring itself according to new input and data. There are feedback loops between the various symbols in the mind, and these particularly come into play when modeling the behavior of other minds (and most especially when modeling itself). How these symbols are expressed in the brain’s architecture is far from clear, but what is clear is that the hardware responds to changes in the software.

Of course, there’s really no way to answer these questions at all until we figure out what consciousness is, and there are so many competing theories about that that we might be a century or more choosing between them. If it’s not clear from the previous paragraph, I’m a Hofstadterian; I believe that consciousness arises from self-sustaining, self-referential patterns of interaction between the various symbols in the brain. I also think that strong AI might in principle be possible; however, I’m also willing to throw a bone to Penrose and consider that the complex interactions between the brain’s hardware and software might be impossible to duplicate on any other substrate.

But, as I said, it’s hard to find the answers when we’re not even sure how to figure out what questions to ask.

Anyway, this is a pretty good example of the kinds of stuff I get into with my sweetie. I’m definitely with the right person.

(Incidentally, she’s currently reading Peter Watts‘ novel Blindsight, and she got very excited while I was reading her the Wikipedia article on the Chinese Room, because Blindsight apparently deals with many many of these issues relating to the nature of cognition. It’s pretty clear that I’m going to have to read the book–if I can ever squeeze it in among all the other stuff I have to read.)

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The path not taken

Oct 29 2009 Published by brian under personal, science

So, last week I sent out this tweet about my mild regret at abandoning my childhood goal of becoming an astronomer. That led to an email exchange with an astronomy student about exactly why and how it happened. I’ve been thinking about it since and thought I’d write something here.

I grew up fascinated by astronomy–the first book I remember owning was about the stars–and it was the only thing I ever really wanted to do up until I entered college. When I did so, I discovered that astronomy was mostly a graduate discipline and I needed a bachelor’s degree in physics first. So I became a physics major.

The only problem with this was the math. I was a straight-A student in math, from elementary school up through my first year of college, so I assumed it wouldn’t be a problem. Sadly, I was wrong. As soon as I started calculus, my grades began to drop. In my three semesters of calc, I had a B, a C (the only one I ever got), and a B. And, if you know anything about the hard sciences, you know that calculus is the beginning of the math you need.

I made it out of calculus somewhat intact, but I continued to struggle through differential equations and linear algebra. And meanwhile, when I started my first upper-division physics classes, I got bogged down with Lagrangians and the calculus of variations. (I’ll forgive you if you can’t read any of the math in those Wikipedia links; I can’t read it myself, anymore.)

Since I was on financial aid at the time, I was on a time limit, and eventually I had to make a decision about whether I could finish the degree before I had to quit. I finally decided I couldn’t. This was devastating, and I had a lot of trouble figuring out what to do. I was too far along with school to finish another major in the time I had left, so I ended up getting a general-studies degree–thinking that I would pick something to specialize in for grad school.

I finished in 1995, worked for a year, and then went back and spent a year working on a master’s in anthropology, planning to go into linguistics (another interest). However, there was very little I could do in that field at my particular school. I eventually left, worked for a number of years, went through a couple of relationships, and then started thinking about library school. A few years later I went for it, and now, of course, I’ve finished (though I still haven’t found a job).

I still haven’t quite forgiven myself for quitting physics, and I do keep up with developments in the sciences. But I’m probably happier now than I would have been if I had continued. If I had followed the career path I was planning on, I’d be a tenured professor now, teaching and writing and doing research–and I’d probably have no social life and an ulcer the size of Nebraska. Instead I have many friends and the time to pursue a wide variety of interests.

Don’t get me wrong, I do have the occasional fantasy about starting over. But I don’t really expect that it’ll happen. I have too many other things I want to do. And I don’t want to have to pull my hair out again trying to deal with the math.

And I do make use of my limited scientific education in my writing, so that’s something!

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