Page:Mind (New Series) Volume 6.djvu/238

222 HOWAED V. KNOX: perception, i.e., of unperceived existence, is of the very essence of the notion of externality. And this again is only another way of saying that the fundamental aspect of the notion appears in that conception of physical events, whereby these are distinguished (as physical events) from the " sub- jective sequence of our apprehension ". It results, indeed, from the considerations adduced in this part, that changes in perception, even when they do not indicate changes in the things perceived, can only be rationalised as functions of physical change : that, in fact, to regard anything as a rela- tively permanent object is to interpret the fluctuations in our perceptions as changes in our bodily relations to the object rather than as changes in the thing itself. Physical permanence has thus no meaning for us except in con- nexion with the flow of physical events. Contrasting the present theory of the nature and value of the notion of externality with others that have been put forward, we can say that not any mere opposition of the extended to the unextended, not any " permanence " of " possibilities of sensation," not any supposed " persistence in consciousness," not any fictitious " regularity in the order of our perceptions " ; but the perpetual flux of the material world, and the fleeting and discontinuous manner in which its parts and processes are presented to consciousness, give scope for (we cannot strictly say, give rise to) the notion of externality. Finally, it is to be noticed that this notion, though appli- cable to experience being, indeed, the necessary condition of the possibility of its rationalisation yet involves a going beyond bare experience. Knowledge therefore, while de- pendent on experience for its material, is dependent for its structure on the activity of thought. Thought is, in fact, essentially the activity of reducing the facts of experience to order. 1 * Science is not a mere description, it is a con- struction. The position we have so far gained, then, may be roughly described as a sort of Kantism though it is obviously devoid of any necessary idealistic implication. The vital point of Kant's idealism (in which point he has been copied by 1 This may be expressed in its biological bearings by saying : that the biological function of thought is so to react on perceptual experience, as to at once analyse it and conceptually enlarge its limits. Human thought differs from animal thought in being (1) purposively directed to the accumulation of results, (2) capable of conscious scrutiny of its own processes. (1) represents the scientific movement of thought, (2) the philosophical.