[5] Yet even writers like Prof. Bain will deny, in the most gratuitous way, that sensations know anything. "It is evident that the lowest or most restricted form of sensation does not contain an element of knowledge. The mere state of mind called the sensation of scarlet is not knowledge, although a necessary preparation for it." 'Is not knowledge _about_ scarlet' is all that Professor Bain can rightfully say. [6] By simple ideas of sensation Locke merely means sensations. [7] Essay c. H. U., bk. ii. ch. xxiii. § 29; ch. xxv. § 9. [8] _Op. cit_. bk. ii. ch. ii. § 2. [9] "So far is it from being true that we necessarily have as many feelings in consciousness at one time as there are inlets to the sense then played upon, that it is a fundamental law of pure sensation that each momentary state of the organism yields but one feeling, however numerous may be its parts and its exposures.... To this original Unity of consciousness it makes no difference that the tributaries to the single feeling are beyond the organism instead of within it, in an outside object with several sensible properties, instead of in the living body with its several sensitive functions.... The unity therefore is not made by 'association' of several components; but the plurality is formed by _dissociation_ of unsuspected varieties within the unity; the substantive thing being no product of synthesis, but the residuum of differentiation." (J. Martineau: A Study of Religion (1888), p. 193-4.) Compare also F. H. Bradley, Logic, book i. chap. ii.