Reid's direct approach to perception

Reid's criticism of the theory of ideas is regarded as his most important philosophical contribution, while his sensation - perception distinction is considered to be his most important psychological contribution. This is surprising since the sensation - perception distinction is one of the basic tenets of the traditional theory of ideas. In order to face this difficulty, I compare Reid's formulation of the sensation - perception distinction with the traditional approach. Contrary to the prevailing opinion, I show that the two formulations differ on essential issues. Consequently, Reid's criticism of the theory of ideas is compatible with his mature view of the sensation - perception distinction (Section I). Understanding Reid's stand in this matter enables us to discuss some features of his direct approach to perception (Section II), and to compare it to a recent psychological formulation of the direct approach as expressed in the Gibsonian, ecological approach (Section III). The discussion shows the relevance and importance of Reid's view for an adequate description of perception.