How do we know this? We don't. We know that they are not concious of the operation going on -- but neither are we concious of the operation of walking. This does not mean that walking somehow occurs without some form of decision making. Whether this decision making is subconcious, proto-receptors, muscular memory, etc it does occur and is still a set of heuristic rules for what to do.

These rules are easily observable in a computer as well as the processing of them. Just because you don't know everything doesn't mean you cannot exclude everything. Suppose I know X was in a house. I don't watch the house, but I do watch the road going south from the house. Now, X is no longer in the house. According to your reasoning saying "I don't know where X went, but I know he didn't go south" is not a proof or reasonable support, but merely naysaying of something, because I don't know where X went

No, you have proof that X did not come south. You do not, in any way at all, have proof that no heuristically based decision making process is going on when a grandmaster immediately prunes his decision tree. You simply have the statement that you don't know what happens.

I think you two are basically arguing over whether the glass is half full or half empty, while the glass in question sits unseen in a locked box in an IBM research park. It is unquestionably true that humans are not performing a complete and exhaustive search down the tree of possible outcomes. The short-term memory buffer limitations of people (even in grandmasters who have greater STM chunking abilites in this domain due to practice) see to that. To the extent that Deep Thought relies on such an approach, then Deep Thought is "un-AI-ish". Now, as you point out, Deep Thought does use strategies for pruning the tree; otherwise it would be unmanageable, even for a supercomputer. Still, within that tree, it still can run through comparisons to a degree so far above that of humans (e.g., without any such thing as STM loss during the comparison process), that this "innate skill" doubtlessly contributes a lot to its ability to play well. Which doesn't sound like human players. Though the tree-pruning part does.

If Abigail's point is just the second sentence back, then he's right. If your point is the following sentence, then you're right, too. Personally, I'd be interested in seeing a detailed analysis of the importance of the strategies vs. what I've called the "skills" of D.T. towards its ability to play well, vis-a-vis human data and well-supported theories on human chess performance. Including a comparison of what you might call "memory-handicapped" versions of D.T. vs. human players. I don't know if any of this sort of thing has ever been published, but I kind of doubt it.

-- Frag.
--
"It's beat time, it's hop time, it's monk time!"

If you're just going to ditch all research and studies done with good chess players (and it really isn't all that hard to ask "did you study the position you'd get after playing a3" to a player), why even bother writing a response?

Abigail

Did you study the force with which to press the keys in typing "did you study the position you'd get after playing a3"? No, but something occured that determine a force within acceptable parameters to do so. But on asking that question you would have to say "No.".

Just because they don't know they did it, doesn't prove that they didn't do it.