Differentiation of Notions of Individual and Class.—As was pointed out just now the coexistence of likeness with unlikeness in the child's experience, may mean one of two things, viz. persistence or identity of one individual object, in spite of certain changes, or a general similarity among a number of different individuals. The process of conception is sometimes described as if the child started with a definite knowledge of individuals and then proceeded to generalise or form a class-idea. There is, however, every reason for saying that the two modes of interpreting likeness-in-difference are reached concurrently and by processes largely similar. Thus it seems most reasonable to suppose that the baby which 'da-das' every bearded person it sees is as yet clearly conscious neither of individuality nor of generality. In other words we must not assume that it is stupidly confounding its sire with a stranger, or, on the other hand, forming an idea of a general class. At this stage the child merely recognises certain interesting similarities and proceeds to express the fact. We have to suppose that the clear apprehension of individual sameness is reached but slowly and in close connection with the first clear consciousness of different things attached by a bond of likeness.
To say that the child's knowledge begins with the concrete individual is not to say that it attains a clear consciousness of what we mean by an individual thing persisting and the same (in spite of change) before it begins to generalise. We must remember that the cognition of a thing as persistent and continuous is the result of lengthy and complex processes of comparative reflection. To individualise is thus to think just as to generalise is to think.[106] In truth, the psychological development of the idea of individuality proceeds along with that of generality, each being grasped as a different way of interpreting partial similarity among our percepts.[107]
[106] Hence the logician can speak of the idea answering to a proper name as a singular concept. See Lotze, Logic, p. 34.
[107] The question of the priority in the individual of the knowledge of the individual or of the general class, the question known as the primum cognitum has been much discussed in connection with the linguistic problem whether names are first used as proper names or as general names.
The Process of Generalisation.—When once this differentiation of the individual idea from the class idea has advanced far enough the process of generalisation proper, or the grasp of common or general qualities, is able to be carried out in the way usually described by psychologists. That is to say, a number of individual things, represented as such, are now compared, the attention withdrawn by a volitional effort, from points of difference and concentrated on points of likeness (abstraction) and so a true process of generalisation carried out.
The common account of the process of conception here followed, as a sequence of three stages, Comparison, Abstraction, and Generalisation, rather describes the ideal form of the process as required by logic than the mental process actually carried out. As we saw above a vague analysis or abstraction precedes that methodical comparison of things by which the abstraction becomes precise and perfect, that is to say, definite points of likeness (or unlikeness) are detected. With regard to generalisation it has been pointed out that a rudimentary form of this process is involved in abstraction. To see the roundness of the ball is vaguely and implicitly to assimilate the ball to other round objects. It is to be added that an imperfect grasp of general features as such (commonly) precedes the methodical process here described. The child realises in a measure, the general function of the name 'horse' before he carries out a careful comparative analysis of the horse-characters. At the same time the use of the word generalisation is important, as marking off the clear mental grasp of the class-idea as such, that is the idea of an indeterminate number, of objects, known and unknown, answering to a certain description.[108]
[108] On the relation of Abstraction to Generalisation see Hamilton's Lectures, Vol. ii, Lec. xxxv.
Conception and Naming.—We have so far supposed that the processes of conception are carried out without any help from language. But it is exceedingly doubtful whether any such orderly process as that just described, the comparison of a number of percepts and the marking off of common attributes could be carried out without the aid of words or some equivalent. It is probable that even the clear grasp of individual things as unities and as permanent identical things, depends on the use of a name (proper name) which as one and the same sound seems to mark in an emphatic way the continued oneness of the object.[109] And the same applies still more manifestly to the apprehension of a general class of things. It is certain that in later life at least all clear general thinking takes place by help of language. The general idea is held together, and retained by means of a name; and, as already pointed out, it is very uncertain whether in the absence of such general signs, the infant or the lower animal ever attains to a clear consciousness of the 'one in the many,' the common aspect of a number of different objects.
[109] It seems to follow that animals cannot attain the clear consciousness of individual things as permanent unities, as we attain it.
Is Generalisation Possible Without Language?—The question how far we can generalise or form a general idea apart from the use of names or other signs is one of the standing cruces in psychology. If we judge by introspective examination of our own minds we do no doubt now and again carry on processes of thought of a quasi-general character with little if any help from words. Yet it is doubtful whether we attain a clear consciousness of the generality of our thinking in this case. It must be remembered too that even if we can, as is alleged, employ a particular image or succession of images as representative of generalities without any aid from language (as when we intuitively follow the proof of a particular case in geometry and at the same time recognise its general validity) we are employing powers of thought that have been developed by help of language.[110]