DAVIS@EMBL.BITNET.UUCP (07/10/87)
Briefly - seems to me that most everyone (including DN himself) has missed out on two key points. First, after Searle, there isn't only *one* AI but two (Searle's strong and weak AI): the first is a suitable target of DN's critique since its whole raison d'etre can be summed up in its idea of AI as `cognitive science', ie; that computer science is a way to approach an understanding of what *existing* intelligent systems do and how they do it. However, let us not forget `weak' AI, which makes no such claims - there is no assumption that the products of weak AI function analagously to "real" intelligent systems, only that they are capable of doing X by some means or another. Second, given that `strong' AI *does* claim to have some intimate relation- ship with cognitive science, its worth asking "is there any other way to study the brain/mind ?". Don Norman castigates (probably correctly) AI for not being a science, but he also fails to point out the likely impossibility of any non-AI-stimulated approaches ever coming to terms with the complexity of the brain. AI models are *NOT* testable!! Just imagine that a keen AI worker comes up with an implementation of his/her model of human brain activity, and that this implementation is so good, and so powerful that it saunters through Mr. Harnad's TTT like a knife through butter.... it is vital to see that there is very little information in this result bearing on the question "is this the correct model of the brain ?". The ONLY way to confirm (test) a `strong' AI model is to demonstrate functionally equivalent hardware behaviour, and psychology is a century or more from being able to do this. Norman seems right to castigate AI workers for excessive speculation unsupported by `real experiments', and undoubtedly, if the aim of `strong' AI is ever to succeed, then we *must* know what it is that we are trying to model, but he should also recognize that AI cannot be tested or developed as other sciences simply because it is unique in studying one domain (computers) with the idea of understanding another (the brain). When AI *is* a science, it will be called psychology.. too long.., paul davis EMBL, Heidelberg, FRG bitnet: davis@embl arpa: davis%embl.bitnet@wiscvm.wisc.edu uucp: ...!psuvax1!embl.bitnet!davis