396 CRITICAL NOTICES is defined as the union of presentational elements in so far as they relate to a single object, or in so far as they are " specifying con- stituents of the same thought" (vol. ii., p. 1). Such synthesis appears already in simple, still more in complex, perception, where no mere union of presented and revived partial experiences consti- tutes the total perception. " The percept of the whole is not the sum of the percepts of the parts" (p. 20). When we perceive what we get is a whole object "schematically apprehended" through various, and often through successive, presentations of some of its parts. The inexperienced parts of the whole we do not necessarily image. We know in advance Jww to hunt for them. We thus schematically anticipate them. Our sense of what the whole object is, is like our sense of the meaning of a word. The parts presented mean the whole, over and above any mere associa- tion of part with part. A good example of this sense of the whole is given by our un visualised apprehension of the insides of objects (p. 24). In general, in perception, one has a " premonition of the whole object " before proceeding to observe or to image the parts. One knows that: "I can if I choose" find or image this or that part not yet presented. This is noetic synthesis (p. 25). It is in- volved on a higher level in "ideal revival" (p. 31). Combined with retentiveness, noetic synthesis gives us " apperception " (p. 40). For " when we consider a noetic synthesis not merely as involved in this or that conscious process, but as a mode of mental grouping which persists as a disposition when it has ceased to operate in actual consciousness, we have the idea of an appercep- tive system". In other words, when we have a revivable system of ideas, or of dispositions that determine ideas, and when this system is such that (p. 115) " its constituents are partial appre- hensions of one and the same whole, so that their relation to each other is conditioned by their relation to the central idea of this whole," such a system is called an apperceptive system. Ex- amples are : mentally conceived plans of action, which are capable of being long held, revived at pleasure, and adapted to various circumstances ; or, again, conscious definitions of classes ; or fashions of intelligent behaviour, such as are involved in speaking French or German instead of English. In all such cases what- ever detailed ideas or images are in consciousness form but parts of one total mental attitude towards some real or ideal whole of objects or ends. The process of apperception itself is the process whereby such an apperceptive system " appropriates a new ele- ment or otherwise receives a fresh determination " (vol. ii., p. 112). Such appropriation involves an assimilation of the new elements to the constitution of the whole system, but cannot be reduced to assimilation (p. 118 sqq.) ; and herein Mr. Stout rightly differs from those Herbartians who conceive that apperception may some- times be purely assimilative. Meanwhile, all such synthetic apprehension of total meanings not only embodies systems of ideas, but fulfils the purposes of
