John Searle 1980a, 1980b, 1990b.
Strong AI: The position that an appropriately programmed computer really is a mind. Computers can possess mental states just by virtue of formal symbol manipulations.
Weak AI: The position that computers are a useful tool in psychology. They help researchers test andn evaluate theories about how the mind works.
From Searle's perspective, Weak AI is an appropriate research program; strong AI is not.