[16] Hence, the only valid distinction that can be drawn between abstraction and generalization is that which has been drawn by Hamilton, as follows: “Abstraction consists in concentration of attention upon a particular object, or particular quality of an object, and diversion of it from everything else. The notion of the figure of the desk before me is an abstract idea—an idea that makes part of the total notion of that body, and on which I have concentrated my attention, in order to consider it exclusively. This idea is abstract, but it is at the same time individual: it represents the figure of this particular desk, and not the figure of any other body.” Generalization, on the other hand, consists in an ideal compounding of abstractions, “when, comparing a number of objects, we seize on their resemblances; when we concentrate our attention on these points of similarity.... The general notion is thus one which makes us know a quality, property, power, notion, relation, in short, any point of view under which we recognize a plurality of objects as a unity.” Thus, there may be abstraction without generalization; but inasmuch as abstraction has then to do only with particulars, this phase of it is disregarded by most writers on psychology, who therefore employ abstraction and generalization as convertible terms. Mill says, “By abstract I shall always, in Logic proper, mean the opposite of concrete; by an abstract name the name of an attribute; by a concrete name, the name of an object” (Logic, i. § 4). Such limitation, however, is arbitrary—it being the same kind of mental act to “concentrate attention upon a particular object,” as it is to do so upon any “particular quality of an object.” Of course in this usage Mill is following the schoolmen, and he expressly objects to the change first introduced (apparently) by Locke, and since generally adopted. But it is of little consequence in which of the two senses now explained a writer chooses to employ the word “abstract,” provided he is consistent in his own usage.
[17] The age here mentioned closely corresponds with that which is given by M. Perez, who says:—“At seven months he compares better than at three; and he appears at this age to have visual perceptions associated with ideas of kind: for instance, he connects the different flavours of a piece of bread, of a cake, of fruit, with their different forms and colours” (First Three Years of Childhood, English trans., p. 31).
[18] Die Seele des Kindes, s. 87.
[19] Taine, Intelligence, p. 18.
[20] Human Understanding, bk. ii., ch. ii., §§ 5-7.
[21] If required, proof of this fact is to be found in abundance in the chapter on “Imagination,” Mental Evolution in Animals, pp. 142-158. It is there shown that imagination in animals is not dependent only on associations aroused by sensuous impressions from without, but reaches the level of carrying on a train of mental imagery per se.
[22] Loc. cit., pp. 397-399. Allusion may also be here conveniently made to an interesting and suggestive work by another French writer, M. Binet (La Psychologie du Raisonnement, 1886). His object is to show that all processes of reasoning are fundamentally identical with those of perception. In order to do this he gives a detailed exposition of the general fact that processes of both kinds depend on “fusions” of states of consciousness. In the case of perception the elements thus fused are sensations, while in the case of reasoning they are perceptions—in both cases the principle of association being alike concerned.
[23] Mental Evolution in Animals, p. 118.
[24] In this connection I may quote the following very lucid statements from a paper by the Secretary of the Victoria Institute, which is directed against the general doctrine that I am endeavouring to advance, i.e. that there is no distinction of kind between brute and human psychology.
“Abstraction and generalization only become intellectual when they are utilized by the intellect. A bull is irritated by a red colour, and not by the object of which redness is a property; but it would be absurd to say that the bull voluntarily abstracts the phenomenon of redness from these objects. The process is essentially one of abstraction, and yet at the same time it is essentially automatic.” And with reference to the ideation of brutes in general, he continues:—“Certain qualities of an object engage his attention to the exclusion of other qualities, which are disregarded; and thus he abstracts automatically. The image of an object having been imprinted on his memory, the feelings which it excited are also imprinted on his memory, and on the reproduction of the image these feelings and the actions resulting therefrom are reproduced, likewise automatically: thus he acts from experience, automatically still. The image may be the image of the same object, or the image of another object of the same species, but the effect is the same, and thus he generalizes, automatically also.” Lastly, speaking of inference, he says:—“This method is common to man and brute, and, like the faculties of abstraction, &c., it only becomes intellectual when we choose to make it so.” (E. J. Morshead, in an essay on Comparative Psychology, Journ. Vic. Inst., vol. v., pp. 303, 304, 1870.) In the work of M. Binet already alluded to, the distinction in question is also recognized. For he says that the “fusion” of sensations which takes place in an act of perception is performed automatically (i.e. is receptual); while the “fusion” of perceptions which are concerned in an act of reason is performed intentionally (i.e. is conceptual).