ABSTRACT
How human beings perceive the world is a traditional field of investigation in Western thought, not only out of anthropocentric curiosity, but also because of the philosophical importance of the question. An answer requires tackling and solving problems concerning both the nature of the world (does an external reality independent of the perceiver exist?) and of humans perceiving that world (how do they do so?). The classic answers fall into two categories: one underlines the greater importance of the external world over the internal world, and the other underscores the exact opposite, the influence exerted by the organism over the external world. Useful reference texts to comprehend the contribution of the various schools to the understanding of perception are those by Bruce and Green (Visual perception, 1992) and by Gordon (Theories of visual perception, 1989).
