This word "meaning," used in a somewhat specialised sense, is a comparatively new importation into psychology. Let me illustrate what it implies by a simple concrete case. A chick, in virtue of its instinctive tendencies, pecks at a small moving insect—a lady-bird—seizes it, throws it on one side, shakes its head, and wipes its bill on the ground. That is the way the situation develops. On the following day it sees such an insect, and may run towards it; but it does not take it into the bill, though it may perhaps wipe its bill upon the ground. The lady-bird has acquired meaning, and in accordance with this meaning the behaviour of the chick is modified. Why not say, as we used to say, that the sight of the insect suggests its nauseous taste, and that the memory of its unpleasant character makes the bird refrain from pecking? Because, in all probability, that is not just what goes on in the mind of the chick, though it does express certain salient features disclosed by our analysis; because it is more likely that the recurrence of the initial stages of the lady-bird situation serve to revive the rest of the situation, including much besides the nauseous taste, if taste it be in the form of a state of expectancy. Be this as it may, the word " meaning," as a general term for what is suggested as the outcome of previous experience, is a convenient one. In this sense, for the child in the nursery, as for the developing animal, the things in its environment are day by day acquiring fresh and fuller meaning, each reviving that part of previous experience which is relevant for practical behaviour.
One can, however, scarcely too strongly emphasise the fact that in passing from biological responses and reactions in the sphere of instinct, as above defined, to intelligent behaviour founded on experience, we introduce a wholly new but supplementary order of values—values not only in terms of organic survival, but also in terms of conscious satisfaction. That situation which has afforded pleasure or has been attended with some form of satisfaction is redeveloped when occasion arises through the presentation of its earlier stages. But that situation which has led to painful results, or from form of discomfort, is not redeveloped. If the earlier stages be presented, the unsatisfactory behaviour is inhibited. The two sets of values—survival values and satisfaction values—are, however, so often and of necessity so predominantly consonant—their inter-relations are so many and so close—that we are apt to forget that they are logically distinct. Physiology, as such, knows nothing whatever of those pleasure-pain values which for the psychologist are essential. They form no part of the ideal construction of physiology: they are dominant factors in the ideal construction of psychology.
And it is here, just where the strictly biological and the distinctively psychological factors begin to interact, that the difficulties of analysis make themselves felt. I have distinguished between the automatic system, the functioning of which is determined entirely by biological values in terms of survival, and the control-system, the functioning of which in its psychological aspect is determined entirely by a different order of values in terms of felt satisfaction. The outcome of the one is instinctive behaviour; the outcome of the other is intelligent behaviour. But both are dependent on heredity. And it is therefore, I think, essential to distinguish, in our ideal construction, between two orders of heredity: first, that which obtains within the automatic system, and which thus determines the nature of the hereditary responses; secondly, that which obtains within the system of intelligent control, and which thus determines the nature of the hereditary likes and dislikes.
For analysis these are independent each within its appropriate sphere; but they are developed within the same organism in close synthetic relationship.
At the outset of individual development instinctive and automatic responses are due to the purely biological order of heredity; but their results are reflected in experience, and therein are subject to the psychological order or heredity, so that the controlling influence of the environment is determined by feeling-tone and values for consciousness. If then we speak of the development of a situation in conformity with the satisfaction it affords, as in accordance with the psychological end, and its development in conformity with the preservation and conservation of the race as in accordance with the biological end, the salient fact is that the two ends are consonant. This has, of course, been fully recognised by evolutionists from Herbert Spencer onwards. I will not here lay stress upon the noteworthy fact, which has not perhaps been sufficiently recognised by the Lamarckian school of evolutionists, that this consonance of biological and psychological end is admitted to be the outcome of the survival of those in which the consonance obtained and the elimination of those in which it was absent—that is to say, is admitted to be dependent on natural selection. I would rather lay stress upon the fact that this consonance affords a striking link of continuity between the more distinctively biological and the more distinctively; psychological factors of the genetic process.
The relation between the two has been well brought out in Professor Groos's discussion of the so-called play of animals. Indeed, such play admirably illustrates the twofold influence of heredity, for on the one hand it is founded on unquestionably instinctive modes of behaviour, and on the other hand it not less obviously appeals to an innate sense of satisfaction. Why do animals begin to play and keep on playing? From the psychological point of view because they like it, from the biological point of view because they thus gain practice and preparation for the serious business of their after life. But why do they like it? Because under natural selection those who did not like it, and therefore did not undergo the preparatory training and discipline of play, proved unfit for life's sterner struggle, and have been therefore eliminated. I have contended that inherited modes of behaviour present to consciousness ready-made situations which develop automatically on biological lines, and that the role of intelligence is to lead to modifications in their redevelopment in accordance with their psychological values. I have also called to remembrance the fact that in the animal world, under normal conditions, these psychological values, with their appeal to feeling, are consonant with biological values in terms of survival. Throughout the course of mental development in the perceptual sphere there is a constant interaction between the two factors broadly classed under the heads "instinct" and "intelligence".