Ecological laws of perceiving and acting: In reply to Fsdor and Pylyshyn (1981)*

This paper is both a reply to Fodor and Pt_lyshyn (198 1) and a systematic explication of one of Gibson’s (1979) basic claims, namely, that there are ecological laws relating organisms tc the a.ffordances of the environment. Gibson’s theory of affordances holds great promise for psychology for a number of reasons: it provides a framework for the precise formulation and testing of hypotheses about behavior and perception (e.g. E. J. Gibson, in press; Johnston and Turvey, 1980; Lee, 19110; Shaw and Bransford, 1977); it suggests a way to integrate theOphenomenological and mechanistic aspects of psychology without succumbing to either one-sided point of view (Reed, 1980; Runeson, 1977;Shaw et al., in press;Tua-:rey and Shaw, 1979); and it promises to put psychology back on the track of seeking lawful relations-as Gibson (1967, p. 122) once said, in science: “You either find causal relations or you do not’“.