The Perception of LIGHT AND COLOUR C.A.Padgham and J.E.Saunders

"It is interesting to digress just for a moment to consider other senses, for example hearing, in which the sensation of loudness is similarly coded and sent to the brain as action potentials in no way different from those of the eye" Pg 48

"A red filter absorbs all the colours of the spectrum except red, which it strongly transmits. This is called selective absorption.We can now see the whole chain of events in the perception of colour (Fig. 4.6). The emission of light and its selective reflection and its progress to the eye are purely physical phenomena, and up to this point there is no colour. As Newton said 'the Rays are not coloured'. But when this modified light enters the ye it is received by the retinal cones which absorb some and in doing so give rise to nerve signals which are interpreted by the brain as a colour perception." Pg 65

"When we come to the higher primate and man, it is of course their possession of larger and more complex brains which enable them to take advantage of the increased information available from their colour-conscious eyes. The fact that in the human colour assumes a great aesthetic importance is of course a bonus, but probably purely an accidental one. Colour to most people plays a very essential and often pleasurable part in their lives." Pg 67