Once, I downloaded a freeware chat program, and used it to chat with with other people in IRC, by pasting the programs reply into IRC and the chatter's replay into the program. I got a girl's phone number that way

Nothing terribly surprising about that; I've certainly known (well, been aware of) plenty of girls who've given their numbers to blockheads... ;/

As for George's proposal, if this "contrarian" does anything more sophisticated than simply adding verbal "nots" to the sentence and repeating it, I should think it would of necessity need either a blockhead construction or else intelligent analytical capacity.

As an alternative to the two schemes described how about constructing an "ironist" or a "contrarian" who twists whatever you say into a paradox or an opposite view? This would require a knowledge (database) of the meanings of words and of grammatical structures, but would just twist the grammatical structures in reply. Well it's an idea; I wonder if its been considered.

In "Darwin's Dangerous Idea" Dennet actually mentions the unreliability of Turing's Test for this very reason.

The usual setup of a Turing test is that the person is explicitly told that one of the participants they are chatting with is a machine, and has to figure out which one that is. An uninformed person can be surprisingly easy to fool; I believe Carl Sagan mentioned in one of his books that the extremely simplistic "Eliza" chat program could not only fool naive people but even caused some of them to develop strong emotional attachments to it. But generally, when a person is alert to the possibility, machines simulating intelligence are fairly easy to detect.

Because it would be branching based on previous data, it must be analyzing some of its data.

Analyzing in the sense I was referring to means performing some sort of transformation or processing on a statement to extract the meaning - analysis in the literal sense of "breaking apart". A Blockhead doesn't analyze any of its incoming data, but just does a bit-by-bit comparison between its input and an entry from its data banks.

We could imagine a Blockhead that stores every possible conversation in a form analogous to a branching tree, where each question and answer represents a decision point that branches out into an innumerable array of possibilities for the next query and reply.

Such a machine would meet this criterion:

Neither of these imaginary constructs perform any actual analysis of their sensory data, and without analysis, there can be no genuine comprehension.

Because it would be branching based on previous data, it must be analyzing some of its data.

I can't shake the feeling I've argued with a few of these…

Once, I downloaded a freeware chat program, and used it to chat with with other people in IRC, by pasting the programs reply into IRC and the chatter's replay into the program. I got a girl's phone number that way...

In "Darwin's Dangerous Idea" Dennet actually mentions the unreliability of Turing's Test for this very reason.

Of course, the vast majority of the time this will result in total gibberish. But if the CCM's output is truly random, all possible outcomes are guaranteed to occur eventually. Once in a great while, its random output will fall into the patterns that code for English characters. Once in an even greater while, these characters will form meaningful words. And once in an unimaginably enormous while, the CCM will apparently respond meaningfully to the most recent thing its interrogator said. It may send a response that dazzles us with penetrating insight, provoke gales of laughter at its razor wit, or respond to our troubles with understanding and sympathy. It may even seem to be aware that its output is purely random, and express its apparent regret that its next reply probably will not be so erudite.

I can't shake the feeling I've argued with a few of these... ^.^