it is merely an expression of individual opinion. The question is:-Can we or can we not explain the dog's action as the outcome of sense-experience, as indicative of intelligence profiting by association? I do not see how this can be denied. The terrier used to start the rabbit nearly every morning, and each time saw it escape into the old drain. There were thus ample opportunities for establishing an association between rabbit and drain. That the sight of the rabbit should suggest the drain into which it daily escaped, and that when the idea was suggested, the dog should run there directly, is a sequence not impossible, one would think, to sense-experience. And if so, the canon of interpretation, so often referred to, makes it imperative for us who adopt it, to accept the interpretation of the action as due to the simpler exercise of intelligence based on senseexperience, rather than that according to which the dog perceived the relation between a chord and its arc.

It is difficult to put the matters we are now discussing to the test of experiment, but wherever an opportunity presents itself we should make the attempt. Some years ago I was with a friend watching a horse which was dragging a heavy load, zigzagging up a steep hill. "How well," said my companion, "that horse appreciates the principle of the inclined plane." I begged him to explain exactly what he meant by this expression. "He sees," said my friend, "that the less the slope the less intense, if more prolonged, the labour to raise the load through a given height." I told him that my own view was that the poor animal was quite unable to perceive the relation between the slope and the labour, and to think "the less the slope the less the labour." Now I have noticed that when I am breasting a steep grassy mountain slope, I have a tendency to slew off to right or left, and thus to lighten my labour. And I thought I might make a few experiments with Toby (which I have subsequently repeated with Tony). I sent him down the slope

b.

again and again, after a small stone. At first, when he was fresh, he came straight up. But as he got tired he began to zigzag. He seemed to slew off in one direction or the other, just as I tend to do myself when I breast a steep slope. When he had slewed off a little way, he looked up at me and made straight for me, gradually slewing off in the other direction. So that the diagram of his course was thus-a being his starting-point, b the spot where I was sitting. There was nothing in the facts observed to negative the interpretation that the zigzagging was the outcome of sense-experience. The dog slewed off the direct course, because he practically found that progression thus was easier. And if the action is possible to sense-experience, we are bound by our canon so to interpret it, and not introduce a perception of the relation between angle of slope and labour involved.

FIG. 20.

a.

I must not bring this chapter to a conclusion without saying, that I freely admit that there are on record anecdotes of animals which I do not think can be readily interpreted as the outcome of sense-experience only, instance the case contributed to Mr Romanes's collection by Mr Haden, of Dundee, of a monkey which wished to mount on to the roof of a hut by means of a door, and finding that the door repeatedly swung to, and thus baulked him, procured a thick blanket which lay in the cage and threw it over the door - the

inference being that he perceived that the blanket would wedge the door open. That was a monkey worth experimenting with. If it really perceived this, and had no previous associations of casual origin on which to found its action, it could perceive other relations which experimental observation would have served to disclose. In the case of the Cebus monkey which Mr Romanes and his sister had for some time under close observation, there is nothing recorded that is not explicable as the outcome of intelligence; or so it appears to me.

On the whole, I am inclined to conclude that when we separate observed facts from observers' inference, there is a remarkably small percentage of cases in which the interpretation, on the assumption of sense-experience only, will not hold good. Such are the cases which should, wherever possible, be made the basis of an experimental investigation. As matters stand at present, I think it far more probable that the small percentage of outstanding cases would, on complete investigation, be shown to be the result of the exercise of intelligence, than that they involve reason in the sense in which I have used this word. I am very far from wishing to occupy the false position of dogmatic denial of rational powers to animals. I think it is a subject for further and fuller investigation. But I do express the opinion that the fuller and more careful the investigation, the less is the satisfactory evidence of processes of reasoning; and that, though the question is still an open one, the probabilities are that animals do not reason.

CHAPTER XVII.

SUBJECT AND OBJECT.

any

T is not my intention to attempt in this work detailed account of the steps by which the faculty of conception, applying its nascent power of analysis and synthesis to the data of sense-experience, impressional and transitional, may have gradually built up a scientific and philosophical interpretation of the world in which we live. The process has been a gradual one, involving several factors. How language would aid in this process I have already briefly indicated. If once, for example, the word "shining" or its equivalent is made symbolic of the conception of a particular quality exhibited by some individual visible object, it forthwith becomes also an instrument both of analysis and of synthesis. Of analysis, because it serves to detach the special quality from other qualities invariably associated with it in experience; of synthesis, because it serves as a centre of aggregation for similar qualities of other objects.

Such a grouping of objects in reference to particular qualities under the influence of the symbolic name, would form an initial stage in the reflective creation of an orderly universe out of the inchoate sequences of sense-experience. A further stage would be reached when the perception of these qualities became an end of conscious endeavour, and man looked out on the world, not merely as a witness, but as an observer. We are all, for example, witnesses of atmospheric changes from year's end to year's end; and perhaps some rough-and-ready generalizations are forced

U

upon us, or are the direct outcome of our native wit.

But we are content, for the most part, to remain mere witnesses. A few of us are, on the other hand, observers. These watch the changes of the weather, with the special object of perceiving the relations involved, and of rising to the conceptions of meteorology. When man thus becomes an observer, he takes an important stride towards the attainment of wider conceptions of the world. And when to observation he adds experiment, which may be described as observation under accurately controlled conditions, he renders his analysis more searching and extends the range of the synthesis dependent thereon. Most important, too, as an aid to the grasping of relations exceeding the reach of immediate perception, is the method of diagrammatic representation. The essence of this process is the translation of all relations, whatever their scope and nature, into visible space relations within the range of immediate perception. A map of a district or country thus condenses to within the reach of immediate perception space-relations of wide extent. An astronomical diagram enables us to grasp the relative sizes and distances of bodies, the actual sizes and distances of which tax the imagination to the utmost. The physicist can in this way represent the relative amplitudes of ether-vibrations of surpassing minuteness. Anything which can be expressed in numerical relations can thus be translated into perceivable space-relations, and thereby, through diagrammatic representation, brought home to the mind through the eye. It is well known that in this way we can represent the fluctuation of prices, deathrate, commercial prosperity and depression, statistics of crime, and numberless other widely different changes. I have used this method in all that I have said concerning the wave or curve of consciousness. Such a curve represents diagrammatically to the eye the relative intensities of numerous factors in consciousness. It, in common with other figures introduced into this book, is a mere diagram, and in