I would restrict the term "intelligence" to the guiding factor in behaviour, as the result of experience, when it falls within what Dr. Stout has termed the perceptual sphere. Here any given situation of practical life is developed in accordance with the meaning which like situations have acquired in the course of their performance. The situations are not analysed: the results of analysis are not rebuilt into ideal constructions by a process of intentional synthesis with a view to explanation and interpretation. That is the outcome of ideational process and conceptual thought.

Throughout the whole range of perceptual development as it is seen in the lower animals there is progressive integration and differentiation of the unit situations, always on essentially practical lines, always in closest touch with active behaviour.

Even perception itself, as genetic psychology has helped us more fully to realise, is dependent on acquired habits of action. Perceptual meaning and value are ever dependent on some activity directed toward that which is so perceived. All differentiations within the presented situations are due to the call for some directed behaviour, are due to the demand for some focussing of active manipulation. Thus is the mouse differentiated for the practical interests of the kitten. And all integration of diverse situations is due to their assimilation in terms of like modes of behaviour in dealing with them, in terms of the similar responses which they evoke. Thus there is an integration of the situations of so-called play and earnest. But in perceptual process, far as differentiation may be carried, it never reaches the stage of intentional analysis; and, far as integration through assimilation may be carried, it never reaches the level of intentional generalisation. These are the results of ideational process.

The influence of the terms we employ, closely connected as it is with our early training, is often deep and abiding. It has been a special merit of Dr. Stout's treatment of psychological topics that he has emphasised, so clearly and in so many ways, the fundamental distinction, as I conceive it to be, between perceptual and ideational process. As he himself has pointed out, one of the great difficulties in the way of its general acceptance is due to the fact that the existing terminology grew up at a time previous to any serious attempt to render clear the distinction. Some of my readers may remember the almost pathetic words in which Dr. Stout laments the misleading influence of the terms we are at present almost forced to employ. If I may be allowed slightly to modify his statement without, as I believe, introducing anything foreign to his thought, his contention is that " human language is especially constructed to describe the mental processes of human beings [in ideational terms], and this means that it is especially constructed so as to mislead us when we attempt to describe the workings of minds which differ in any great degree from the human" and even the workings of our own minds on the perceptual plane. "A horse having had a feed at a certain place one day, stops of his own accord at that place on a second journey. People say that it remembers being fed here before, and infers that it will be fed here again. In all probability these words with their human implications [on the ideational plane] are quite misleading. Suppose that the master of the horse is a bibulous person, who takes a drink as a matter of course whenever he comes to a public-house on the road. In order to do this he need not go through the process of [looking back retrospectively on his past experience and in this sense] remembering that he has had a drink at a public-house before, or of [drawing a definite, logical conclusion and in this sense] inferring that he can have a drink at a public-house again. He simply has a bias to stop at a public-house whenever he comes to one. Probably the horse's act implies just as little of remembering or inferring".

It will be noticed that the difficulty which Dr. Stout indicates does not apply only to the mental processes of the horse, but also to some at least of those which are characteristic of his bibulous master. No doubt, taking men and women as we find them, there is the closest interaction between ideational and perceptual process, just as there is between instinctive and intelligent procedure. But there is, I conceive, an analogous relation. Just as the instinctive factor provides data which intelligence deals with so as to shape it to more adaptive ends, so does the perceptual factor provide the more complex data which, through ideational process, are raised to a yet higher level in rational conduct. And in both cases notwithstanding may, largely in consequence of the closeness of the interaction., it is the business of analysis to distinguish with the utmost clearness the essential features of the constituent factors.

I take it that the leading characteristic of perceptual process is the dealing with situations as wholes in their unanalysed entirety. When the integration of which I have spoken has been carried far, any relatively new situation is assimilated to the past experience gained in similar situations wherein certain salient features have been differenciated through their intimate relations to practical activities. The associations thus begotten are not associatins betwen seperate ideas, but in every case essentially between the situation and the practical behaviour it calls forth. Even this expression savours too much of analysis. Let us rather say that the type of association distinctive of perceptual process is that between ena early phase of a situation and the succeeding phase, so that what is suggested in any given case is a mode of development of the situation as a whole through practical behaviour.

In a certain way; it is the meaning which attaches to the public-house as the result of practical experience on the part of the horse and of his bibulous master.