“What I particularly wish to observe,” says an experienced naturalist, “is that there are good reasons for supposing that elephants possess abstract ideas; for instance, I think it is impossible to doubt that they acquire through their own experience notions of hardness and weight, and the grounds on which I am led to think this are as follows. A captured elephant, after he has been taught his ordinary duty, say about three months after he is taken, is taught to pick up things from the ground and give them to his mahout sitting on his shoulders. Now for the first few months it is dangerous to require him to pick up anything but soft articles, such as clothes, because the things are often handed up with considerable force. After a time, longer with some elephants than others, they appear to take in a knowledge of the nature of the things they are required to lift, and the bundle of clothes will be thrown up sharply as before, but heavy things, such as a crowbar or piece of iron chain, will be handed up in a gentle manner; a sharp knife will be picked up by its handle and placed on the elephant’s head, so that the mahout can also take it by the handle. I have purposely given elephants things to lift which they could never have seen before, and they were all handled in such a manner as to convince me that they recognised such qualities as hardness, sharpness, and weight.” Lloyd Morgan, who, in his books on comparative psychology, is evidently disposed to concede as small a measure of intelligence to animals as possible, comments upon the above observation as follows:[12] “Are we to suppose that these animals possess abstract ideas? I reply—That depends upon what is meant by abstract ideas. If it is implied that the abstract ideas are _isolates_; that is, qualities considered quite apart from the objects of which they are characteristic, I think not. But if it be meant that elephants, in a practical way, ‘recognise such qualities as hardness, sharpness, and weight,’ as _predominant_ elements in the constructs they form, I am quite ready to assent to the proposition.” I agree fully with this conclusion, adding the one remark that between the pure abstract notion and the “predominant” notion so called, there is only a difference of degree. If the predominant element is not isolated, detached, and fixed by a sign, it is certainly near being so, and deserves on this ground to be called an abstract of the lower order. The observation of Houzeau has been frequently quoted respecting dogs, which, suffering from thirst in arid countries, rush forty or fifty times into the hollows that occur along their line of march in the hope of finding water in the dry bed. “They could not be attracted by the smell of the water, nor by the sight of vegetation, for these are wanting. They must thus be guided by general ideas, which are doubtless of an extremely simple character, and, in some measure, supported by experience.”