Sir Francis Galton writes:

“Those who find a difficulty in understanding how a feebly felt mental action can vanquish a strong desire, will find the difficulty vanish if they consent to assume a physiological and not a psychical standpoint. The gain is as great as viewing the planetary system after the fashion of Copernicus, instead of that of Ptolemy. There is nothing contrary to experience in supposing that conflicting physiological actions may be perceived with a distinctness quite disproportionate to their real efficacy. We may compare the conflict between faintly perceived activities of one kind and clearly perceived activities of another kind, to that between troops dressed in a uniform scarcely distinguishable from the background with others clad in staring scarlet. We must be content to admit that our consciousness has a very inexact cognisance of the physiological battles in our brain, and that the mystery why apparently weak motives of one class should invariably get the better of apparently strong motives of another class, lies wholly in the word ‘apparently’. In short, that the appearances of their relative strength are deceptive”.