Abstract

Call u the triplet of cone quantum catch for the light that is incident on a surface, and v the triplet of cone quantum catch for the light that is reflected off that surface. Philipona & O'Regan (2006) present results from numerical calculations showing that: 1. each surface can be associated with a 3 by 3 matrix A such that the relation v = A u to a very high degree of accuracy for any natural illuminant, 2. the vast majority of such matrices associated with Munsell chips have three real eigenvalues, 3. Munsell chips that are most often given a name in the World Color Survey are chips whose associated matrices have a singular configuration of eigenvalues, as measured by a "singularity index". The conclusion of the paper is that this striking coincidence lends credence to the idea that data about color naming derive from facts about natural lights, surface reflexion properties, and human photopigments, rather than from facts about neural pathways or cortical representations.