The more I think about Watson, the more I'm astounded about what IBM has done here. This isn't just some glorified answer engine. If you think about what this system has to do to get these questions right, you quickly realize that there's a lot more going on behind the scenes.
At its core, Watson is an expert answer engine that utilizes natural language processing technology.
And it's probably doing it in a way that's very, very close to how the human brain does it. I'd be willing to bet that the processes behind Watson's programming is very analogous to how the human mind goes about it. Watson, which has access to a massive repository of information, has to interpret all the nuances of language—synonyms, puns, slang, and all—and quickly come up with an answer. It typically builds a list of around four to five answers, and based on a probability analysis, selects what it thinks is the most likely answer. I'm almost certain that the human mind goes about it in the exact same way. It has been suggested, for example, that the mind applies Bayesian probabilism in its calculations. Wouldn't be amazing if we eventually discover that even the algorithms are the same? If this is the case, then IBM has actually created a stand-alone module of the human brain.
So, in terms of the rule based AI vesus whole brain emulation debate, you can strike this down as a victory for the former.
The big difference, of course, is that Watson is not conscious. But that doesn't make a difference. You are not conscious, either, of how you process natural language, access the memory stores in your brain, and come up with an answer. Your brain does this for you behind the scenes and presents the answer to your consciousness; you're none the wiser. You only think you're clever, and that "you" came up with the answer, but in reality the unconscious mechanistic parts of your brain did all the work.
Some people may complain or freak out about that, but I think it's rather cool. We're biological robots; get over it.
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