Daniel C Dennett Three Kinds of Intentional Psychology 1981英文电子书.pdf

Three Kinds of Intentional Psychology Daniel Denneft Suppose you and I both believe that cats eat fish. Exactly what feature must we share for this to be true of us? More generally, recalling Socrates favorite style of question, what must be in common between things truly ascribed an intentional predicate-such as wants to visit China or expects noodles for s ~ p p e r ?As~ Socrates points out, in the Meno and elsewhere, such questions are ambiguous or vague in their intent. One can be asking on the one hand for something rather like a definition, or on the other hand for something rather like a theory. (Socrates of course preferred the former sort of answer.) What do all magnets have in common? First answer: they all attract iron. Second answer: they all have such-and-such a microphysical property (a property that explains their capacity to attract iron). In one sense people knew what magnets were -they were things that attracted iron-long before science told them what magnets were. A child learns what the word magnet means not, typically, by learning an explicit definition, but by learning the folk physics of magnets, in which the ordinary term magnet is embedded or implicitly defined as a theoretical term.3 Sometimes terms are embedded in more powerful theories, and sometimes they are embedded by explicit definition. What do all chemical elements with the same valence have in common? First answer: they are disposed to combine with other elements in the same integral ratios. Second answer: they all have such-and-such a microphysical property (a property which explains their capacity so to combine). The theory of valences in chemistry was well in hand before its microphysical explanation was known. In one sense chemists knew what valences were before physicists told them. So what appear