In the child we find a tendency to act in certain ways toward all objects, events, etc., which are in any respect alike. After learning to use the hands, for example, for a certain act, the same hand movements are afterward used for other similar acts which the child finds it well to perform. He thus tends, as psychologists say, to "generalize," that is, to take up certain general attitudes which will answer for a great many details of experience. On the side of the reception of his items of knowledge this was called Assimilation, as will be remembered. This saves him enormous trouble and risk; for as soon as an object or situation presents itself before him with certain general aspects, he can at once take up the attitude appropriate to these general aspects without waiting to learn the particular features of the new. The ability to do this shows itself in two rather different ways which seem respectively to characterize man on the one hand and the lower animals on the other. With the animals this tendency to generalize, to treat objects in classes rather than as individuals, takes the form of a sort of composition or direct union of brain pathways. Different experiences are had, and then because they are alike they tend to issue in the same channels of action. The animal is tied down strictly to his experience; he does not anticipate to any extent what is going to happen. He does not use one experience as a symbol and apply it beforehand to other things and events. He is in a sense passive; stimulations rain down upon him, and force him into certain attitudes and ways of action. As far as his knowledge is "general" it is called a Recept. A dog has a Recept of the whip; so far as whips are not too different from one another, the dog will act in the same way toward all of them. In man, on the other hand, the development of mind has gone a decided step further. The child very quickly begins to use symbols, words being the symbols of first importance to him. He does not have, like the brute, to wait for successive experiences of like objects to impress themselves upon him; but he goes out toward the new, expecting it to be like the old, and so acting as to anticipate it. He thus falls naturally into general ways of acting which it is the function of experience to refine and distinguish. He seems to have more of the higher sort of what was called above Apperception, as opposed to the more concrete and accidental Associations of Ideas. He gets Concepts, as opposed to the Recepts of the animals. With this goes the development of speech, which some psychologists consider the source of all the man's superiority over the animals. Words become symbols of a highly abstract sort for certain classes of experiences; and, moreover, through speech a means of social communication is afforded by which the development of the individual is enormously advanced.