The central characteristic of cognitive explanations of behavior is the appeal to inner representations. I examine the grounds which justify representational explanations, seeking the minimum conditions which organisms must meet to be candidates for such explanations. I first discuss Fodor's proposal that representationality be attributed to systems which respond to nonnomic properties, arguing that the distinction between the nomic and nonnomic in perception is fatally ambiguous. Then I turn to an illustrative review of the behavior and neurobiology of Hermissenda crassicornis, (...) a marine mollusk. Concerning this "model system," I compare the representational style of explanation with both behaviorist and neurophysiological explanations. Representational explanation is potentially more comprehensive than its rivals, and thus I conclude that representations are useful posits wherever internal information-bearing states mediate behavior. (shrink)

Each of the following might be considered both necessary and sufficient for an organism to count as a psychological organism: (a) being able to do something that requires a psychological theory to explain; (b) being capable of having experiences; (c) being motivated; (d) behaving in ways that are the joint outcome of the organism's beliefs and desires; (e) being capable of instrumental learning, or operant conditioning; (f) being susceptible to classical conditioning. This paper takes up each of these candidates in (...) turn in an effort to clarify what the idea of a psychological organism really is. An argument is sketched for saying that (f) yields the weakest version of the idea of a psycholgical organism, that (e) yields a stronger version, and that (d) yields an even stronger one. What these versions have in common makes them all versions of a single idea. (shrink)