On Seeing Reddish Green and Yellowish Blue

Science  09 Sep 1983:
Vol. 221, Issue 4615, pp. 1078-1080
DOI: 10.1126/science.221.4615.1078


Four color names—red, yellow, green, and blue—can be used singly or combined in pairs to describe all other colors. Orange, for example, can be described as a reddish yellow, cyan as a bluish green, and purple as a reddish blue. Some dyadic color names (such as reddish green and bluish yellow) describe colors that are not normally realizable. By stabilizing the retinal image of the boundary between a pair of red and green stripes (or a pair of yellow and blue stripes) but not their outer edges, however, the entire region can be perceived simultaneously as both red and green (or yellow and blue).