Theories of Trichromatic Vision

Abstract

THERE are frequent discussions concerning the rival hypotheses of colour vision, but seldom, if ever, do we see discussed the relative positions of the two rival theories of trichromatic vision. There are two possible plans which present different advantages. These are: (1) That eaoh cone of the retina is able to respond to every one of the three kinds of sensation, red, green and blue; (2) that there are three entirely different kinds of cone, one for the sensation of red, one for the sensation of green, and one for the sensation of blue. The advantages and disadvantages of these two rival hypotheses will now be considered in turn.