Experience

For this very general function there is no wholly satisfactory term. If "Cognition" is retained, care must be taken to avoid, in a purely psychological treatment, epistemological implications. In the theory of knowledge, as often in every day speech, what is said to be cognised is thereby implied to be "true." The term in fact is restricted to what, from the psychological point of view, may be the end or terminal state of a complex process, and possesses in addition certain characters in virtue of which it is recognised as true. With these criteria the psychologist as such is not concerned, except in so far as the marks of truth are discovered by the experient himself in the course of his development. In psychology, however, the term "cognition" is re quired to cover the process as a whole. Believing and supposing are in the psychological sense cognitive processes. But how far what is supposed or believed really is as it is supposed or believed to be is not properly a psychological question. It is not indeed a question which the psychologist can safely ignore. In tracing the conditions under which a belief arises, it makes an impor tant difference whether the belief is assumed to be false or true. But whether it is false or true cannot primarily be decided on psychological grounds but on grounds which the psychologist shares with others. The appeal is primarily to common sense and science. It is only in a secondary way that the psychologist can supply relevant data. Where there is otherwise room for doubt, he may show that the psychological conditions are such as to account for the genesis of a belief, without assuming it to be true or even assuming it to be false. Is a mountain which looks near really near? It is relevant to this question to point out that whether it is near or far it would for psychological reasons seem to be near.

The Development of Cognition.

Two closely connected problems are presented ; to trace the development of the know ing function, and to disentangle the various phases of growth in our apprehension of the world in which we live and of ourselves as agents. In these inquiries we have to determine the primary and irreducible elements with which development could theoreti cally begin, and to formulate the laws of growth by the opera tion of which our present complexity of experience has been brought about.

It is clear that we can start neither from blank unconscious ness nor from any absolute beginning. If conscious life has had a beginning at all the point of its emergence is not known, nor can we observe such forms of experience as we plausibly postu late in primitive animal life. What is literally irreducible may perhaps never be known. It is sufficient, however, to treat as primitive that which resists analysis and cannot be derived by accepted genetic laws. How, then, are such laws to be known? The answer might also naturally seem to depend upon the evi dence of primitive experience, and the difficulty has sometimes been supposed to constitute an objection to any serious attempt to solve the problem at all. There are, however, means at our

disposal. The conscious life of which we have immediate aware ness is consciousness in process of development, and from such changes as we there observe the principles of growth can be defined.

Primary Laws.

"Suppose that in the course of a few min utes we take half a dozen glances at a strange and curious flower. We have not as many complex presentations, which we might symbolize as . . : But rather, at first only the general outline is noted, next the disposition of petals, stamens, etc., then the attachment of the anthers, position of the ovary, and so on that is to say, symbolizing the whole flower as (p' [ab] s' [cd] o' [fg]), we first apprehend, say (p' s' o'), then (p' [ab] s'. . o'. . ) or (p' [a . ] s' [c . o' [f . .]) and so forth." The case, adduced by Ward (Psychological Principles, p. 81), provides in miniature an example of the principal laws with which we are concerned. The changes admit of precise determination by experimental methods. If the object is exposed in momentary flashes by means of an instrument through which the duration of the appearance and other conditions can be accurately controlled, the phases of cognitive growth admit of clear delineation.

In general, we find that when the object is a complexly varie gated whole the context immediately apprehended undergoes a process of differentiation either until its detail is exhausted or until certain limits are reached which are set by the so-called "span of attention" and the observer's powers of discrimination. Certain phases of this growth call for special attention.

(a) Differentiation.—Sense experience is sensibly continu ous, each fresh item intruding not as something absolutely new, not as a presentation replacing a total absence of experience, but as a change in a pre-existent sensible field, part of which remains as a relatively indeterminate background. The darkness which is experienced in the absence of external stimulation is wholly dif ferent from the insentience of a stone. What is earlier in the process is usually lacking in variety. At first a cloudless sky will appear as a uniform blue, but attention will reveal a variety of hues between the zenith and the horizon. Differentiation which in normal perception occurs with extreme rapidity admits of detailed analysis, when, by experimental means, this process is slowed down. Under such conditions a definite order is observed in the emergence of specific colours and forms—an order which perhaps more or less accurately repeats that of cognitive development in the race. Despite the marked contrasts which now obtain between the specific qualities of a given sense the variety they manifest has only come about by slow degrees. This well may be the case with regard to the more fundamental difference of modality as well, for the hypothesis finds indirect support from the physiol ogy and pathology of the receptive organs, and from what is known of sentience in the lower animals.