With the consciousness of the real the elementary practical requirements are generally secured, and the illusory appearances are allowed for or ignored. In fact, however, the experient does not leave the matter here. Incoherence in experience, like any form of problem, provides a motive for further activity of atten tion. Moreover, the data from illusions are of practical utility, and assist the growth of knowledge in other ways. Variation in the appearance of an object may provide no information about its intrinsic nature, but through it knowledge is obtained of the medium in which it stands and of the embodied self as percipient.
In the course of our practical dealings with physical things, sense-presentations arise and change in various ways independently of our own activity. In this way knowledge is primarily gained with regard to objects other than ourselves. When however, changes occur concomitantly with and follow from the exercise of our volition, we obtain a fuller apprehension of the nature and powers of the embodied self. But we cannot sharply divide sensation into two separate groups, those which are wholly inde pendent of ourselves and those which are wholly dependent. In general changes which are partly independent and partly depend ent on ourselves occur in all alike. Hence through the same sensible change knowledge is gained concerning both ourselves and other things. But what is only apparent change in external objects means real change in the percipient self, or in the medium of perception. "Appearance" and "reality" are thus relative terms. Nothing is mere appearance, nothing sheer illusion. Originally knowledge is vague and confused. Attributes within the presented field are loosely and indiscriminately referred. But the properties of things are gradually sorted out, as being either the real and inherent properties of the thing perceived, or of the medium through which we apprehend it, or of the organs of the self. Before discrimination is complete the real properties of one thing are the apparent properties of another, but nothing which enters into perception would seem to be able to stand as the property of nothing at all. There is no doubt a tendency to refer too much to that which at the time is the centre of interest—usually the physical thing perceived—and too little to the medium through which it is observed, and hardly anything at all to the organ of perception.
So far then from our apprehension of the world commencing in the awareness of "subjective modifications" giving rise to a sub sequent process of "projection" of their properties to external physical things, the reverse description would be much nearer the truth. If anything, we start with an objective bias, and what is most inward is the last to be observed. A long inductive inquiry is required in order to determine just where each property is properly to be referred. The process serves to illustrate the fact
that "scientific method" is implicit in cognitive development throughout. Our pre-scientific knowledge both of the external world and of the embodied self involves the use of principles which later may admit of explicit formulation and deliberate use. The employment of hypothesis, the search for verification and the use of "methods of induction" so far from being superimposed at the level of pure conceptual thought are implicitly involved at every stage. Conceptual formulation arises from reflective analysis upon processes which have practically been employed without abstract formulation or generalised expression. Here, as elsewhere, science is but the refinement and extension of common sense.
In reviewing the functions of the embodied mind, priority of treatment, in conformity with tradition, has been accorded to cognition. It is, however, very widely held that priority belongs by natural right to the experience of conation. Primarily, it is said, we are practical beings, we cognize only as a means to action. It would further seem to be implied that cognition as divorced from practical action is a late and unnatural growth.
We can in fact go further and assert that cognition is itself a mode of action, and any separation is possible only by abstrac tion. This, however, can be granted whilst denying priority either way. If mere cognition is an abstraction, conation divorced from it is unintelligible. The object of conation must be also in some manner an object of apprehension.
In the study of conation we return to the problems which are central from the objective point of view; for the experience of conation is the normal psychical antecedent to a bodily movement. But many psychologists have been curiously unwilling to endorse this common sense opinion that an action is normally the outcome and expression of a wish or of our wanting some change in a given situation. It is often said, for example, that for a move ment to occur all that is necessary is that attention be directed to a representation of that movement or of its effects. This is the doctrine of ideo-motor action. It fails, however, to do justice to the unique and irreducible nature of conative experience and to assign it any intelligible function when it in fact occurs. Whilst "wanting" implies attention the latter does not exhaust the mean ing of the former. It is in fact only a special case. Attention is conation directed to further cognition. Bodily action, however, implies more than curiosity with regard to the presentation of movement. We want the movement to occur and external effects to be produced. We shall find that a more coherent theory of behaviour can be founded on the view that conative action is primary and that ideo-motor and even reflex action are specific types of simplification of what was originally more complex.