And first a few words on this most conspicuous distinction which thesenames imply. Manifestations that occur under the conditions called thoseof perception (which conditions we must separate from all hypotheses, andregard as themselves a certain group of manifestations) are ordinarily farmore distinct than those which occur under the conditions known as thoseof reflection, or memory, or imagination, or ideation. These vivid manifestationsdo, indeed, sometimes differ but little from the faint ones. When it is nearlydark we may be unable to decide whether a certain manifestation belongs tothe vivid order or the faint order -- whether as we say, we really see somethingor fancy we see it. In like manner, between a very feeble sound and the imaginationof a sound, it is occasionally difficult to discriminate. But these exceptionalcases are extremely rare in comparison with the enormous mass of cases inwhich, from instant to instant, the vivid manifestations distinguish themselvesunmistakeably from the faint. Conversely, it now and then happens (thoughunder conditions which we distinguish as abnormal) that manifestations ofthe faint order become so strong as to be mistaken for those of the vividorder. Ideal sights and sounds are in the insane so much intensified as tobe classed with real sights and sounds -- ideal and real being here supposedto imply no other contrast than that which we are considering. These casesof illusion, as we call them, bear, however, so small a ratio to the greatmass of cases, that we may safely neglect them, and Say that the relativefaintness of manifestations of the second order is so marked, that we arenever in doubt as to their distinctness from those of the first order. Orif we recognize the exceptional occurrence of doubt, the recognition servesbut to introduce the significant fact that we have other means of decidingto which order a particular manifestation belongs, when the test of comparativevividness fails us.
Manifestations of the vivid order precede, in our experience, those ofthe faint order. To put the facts in historical sequence -- there is firsta presented manifestation of the vivid order, and then, afterwards. may comea represented manifestation that is like it except in being much less distinct.
After having those vivid manifestations known as particular places and personsand things, we can have those faint manifestations which we call recollectionsof the places, persons, and things, but cannot have these previously. Beforetasting certain substances and smelling certain perfumes, we are withoutthose faint manifestations called ideas of their tastes and smells; and wherecertain orders of the vivid manifestations are shut out (as the visible fromthe blind and the audible from the deaf) the corresponding faint manifestationsnever come into existence. It is true that special faint manifestations precedethe vivid. What we call a conception of a machine may presently be followedby a vivid manifestation matching it -- a so-called actual machine. But inthe first place this occurrence of the vivid manifestation after the faintis not either spontaneous or easy like that of the faint after the vivid.
And in the second place, though a faint manifestation of this kind may occurbefore the vivid one answering to it, yet its component parts may not. Withoutthe foregoing vivid manifestations of wheels and bars and cranks, the inventorcould have no faint manifestation of his new machine. Thus it cannot be deniedthat the two orders of manifestations are distinguished from one anotheras independent and dependent.
