We may say, then, that the higher phases of mental development are characterized by the fact that the situations contain the products of reflective thought, presumably absent in the earlier stages; they are further characterized by a new purpose or end of consciousness, namely, to explain the situations hitherto merely accepted as they are given in presentation or re-presentation; they require deliberate attention to the relationships which hold good among the several elements of successive situations; and they involve, so far as behaviour is concerned, the intentional application of an ideal scheme with the object of rational guidance. We shall follow Dr. Stout in terming this later stage of mental development the ideational stage; and in speaking of the simpler situations considered in the preceding section as belonging to the perceptual stage.

It should be observed that we are not attempting to determine just where, in the scale of organic existence, the line between the perceptual and the ideational stages of mental development is to be drawn. We are certainly very far from asserting that the one does not give rise to the other in the course of an evolution which is orderly and progressive. We are merely contrasting the rational guidance of effective consciousness at its best with the earlier embryonic condition out of which it has arisen by natural genesis. In doing this we have been forced to make some reference to the difficulties of technical nomenclature. And some further reference is necessary lest our point of view be misunderstood.

We shall regard these abstract and general ideas as the products of an intentional purpose directed to the special end of isolating the one and of classifying the other; we shall reserve the term rational for the conduct which is guided in accordance with an ideal scheme or deliberate plan of action; while for behaviour to the guidance of which no such reflection and deliberation seems to have contributed we shall reserve the term intelligent. If, for example, the rejection of a cinnabar caterpillar by the chick is the direct result of experience through the re-presentation in the new situation

of certain elements introduced during the development of a like situation, we shall call it an intelligent act. But if we have grounds for supposing that the situation is reflectively. considered by the chick in relation to an ideal and more or less definitely conceived plan of action which is (perhaps dimly) taking form in its mind, we shall regard it as so far rational. And so, too, in other cases of animal behaviour. Now, with regard to the control through which consciousness is effective in the guidance of behaviour, it is necessary, in view of these considerations, to distinguish its intelligent from its rational exercise. And this is of importance since we generally speak of control in the latter sense in reference to human conduct. Intelligent control (on the perceptual plane) is due to the direct operation of the results of experience without the intervention of any generalized conception or ideal. In rational control (on the ideational plane), such conceptions and ideals exert a controlling influence. If, to prevent a boy sucking his thumb we administer bitter aloes, we trust to intelligent control through the immediate effects of experience; but if he be induced to give up the habit because it is babyish, he so far exercises rational control. What we call self-control is of this type. Only one more distinction need be drawn. Intelligent behaviour, founded on direct association gained through previous experience, we shall attribute to impulse; but for rational conduct, the outcome of reflection and deliberation, we seek to ascertain the motive. In human affairs our motives are referred to certain categories each of which presupposes an ideal scheme, prudential, æsthetic, ethical, or other. To act from motive and not from impulse is to act deliberately, because we judge the action to be expedient, seemly, or right, as the case may be. If, then, we contrast the lower perceptual stages of mental evolution with the higher ideational phases, the former includes behaviour due to impulse; but from it conduct due to motive is excluded.

IV. THE EVOLUTION OF CONSCIOUSNESS

The origin of consciousness, like that of matter or energy, appears to be beyond the pale of scientific discussion. The appearance of effective consciousness on the scene of life does indeed seem to justify the belief in the prior existence of sentience as the mere accompaniment of organic behaviour. Ex nihilo nihil fit. And since effective consciousness must, on this principle, be developed from something, it is reasonable to assume that this something is pre-existing sentience. Again, we may assume that this sentience is a concomitant of all lifeprocesses, or only of some. But we have no criterion by which we can hope to determine which of these alternatives is the more probable.

We appear, however, at all events to have evidence that when effective consciousness docs enter on the scene and play its part in the guidance of behaviour, its progress is, in technical phraseology, marked by that differentiation of conscious elements, and that integration of these differentiated items, which are seemingly the correlatives of the differentiation and integration of nervous systems. There is thus, presumably, a progressive development of orderly complexity in the conscious situations of which controlled or guided behaviour is the outcome. And when this has reached a certain stage-what stage it is most difficult to determine the relationships, at first implicit in the conscious situations, as they naturally arise in the course of experience, begin to be rendered explicit with the dawn of reflection. Intentional abstraction and generalization to which data are afforded by the reiterated emphasis in experience of the salient features in successive situations, supply new elements to the more highly developed situations of rational life. Ideal schemes and plans of action, the products of reflection and foresight, take form in the mind and enter into the conscious situation. And the intelligent animal, hitherto the creature of impulse, guided only by the pleasurable or painful tone which gives colour to experience, becomes

a rational being, capable of judging how far his own behaviour and that of others is conformable to an ideal.

If, then, we were asked to characterize in the briefest possible terms the stages of conscious evolution, we should say that in the first stage we have consciousness as accompaniment; in the second, consciousness as guide; in the third, consciousness as judge. And if we were pressed to apply distinctive terms to these three, we should adopt St. George Mivart's term consentience for the mid-phase, and speak of mere sentience in the first stage; consentience in the second; and consciousness, with restricted signification, in the third and highest stage. Such a distinction in terms is, however, a counsel of perfection, and we shall not attempt to preserve it in the following pages, in which the word "consciousness" will be used in a comprehensive sense.

CHAPTER III

INSTINCTIVE BEHAVIOUR

I. DEFINITION OF INSTINCTIVE BEHAVIOUR

THERE are probably few subjects which have afforded more material for wonder and pious admiration than the instinctive endowments of animals. "I look upon instinct," wrote Addison in one of his graceful essays, "as upon the principle of gravitation in bodies, which is not to be explained by any known qualities inherent in the bodies themselves, nor from any laws of mechanism, but as an immediate impression from the first Mover and the Divine Energy acting in the creatures.' In like manner Spence said: "We may call the instincts of animals those faculties implanted in them by the Creator, by which, independent of instruction, observation or experience, and without a knowledge of the end in view, they are all alike impelled to the performance of certain actions tending to the wellbeing of the individual and the preservation of the species."† According to such views, instinct is an ultimate principle the natural genesis of which is beyond the pale of explanation. But similar views were, at the time these passages were written, held to apply, not only to animal behaviour, but also to animal structure. The development of the stag's antler, or of the insect's wing, was also regarded as "an immediate impression from the first Mover and the Divine Energy acting in the creatures." This view, however, is, neither in the case of

Spectator, No. 120.

Kirby and Spence, "Introduction to Entomology," Letter xxvii. p. 537 (7th Edit., 1858).

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