Only a very short time after the formal birth of information theory in 1948 (Wiener, Shannon) its potential value in psychology began to be realized (Miller and Frick, 1949). Quine's influential suggestion (1968) that epistemology be naturalized, i.e., be viewed as a branch of psychology, might have been expected to bring information theory into epistemology but has not. Philosophers have regularly looked at the Shannon and Wiener definition and then declared that philosophers ought to be concerned about a different concept of information (Bar-Hillel, 1952, Hintikka and Suppes, 1970). More recently, Dretske (1981) makes information central to epistemology, but not in the sense defined by Shannon and Wiener. Instead he introduces his own alternative definition. Meanwhile in psychology, Gibson (1966) has proposed an "ecological theory of perception" which makes information central, but he too rejects the S&W (Shannon and Wiener) definition (1966, p. 245). I will review both Dretske's and Gibson's reasons for rejecting the standard definition and argue that their reasons are defective. I conclude, however, by arguing that from the point of view of a naturalized ecological epistemology one must go beyond the standard definition and include other considerations.