Apart from the variations in group customs and traditions, and their progressive application to changing circumstances which individuality makes possible, it cannot be too strongly emphasized that society is the name for the process by which individuals live together. It is the individuals who are the realities and the happiness of individuals which is the aim of social organization. Such happiness is only attainable when individuals are allowed to make the most of their native capacities and individual interests. The social group as a group will be more interesting, colorful, and various when every experimentation and variety of life are encouraged and promoted. And the individuals in such a society will be personalities, not the mere mechanisms of a regimented routine.
CHAPTER IX
INDIVIDUAL DIFFERENCES
The meaning of individual differences. The major part of this volume has been devoted to a consideration of those traits, interests, and capacities which all individuals share, and which may in general be described as the "original nature of man." These distinctive inborn tendencies were treated, for purposes of analysis, in the most general terms, and, on the whole, as if they appeared in the same strength and variety in all individuals. When we thus stand off and abstract those characteristics which appear universally in all individuals, human nature appears constant. But there are marked variations in the specific content of human nature with which each individual is at birth endowed. Put in another way, one might say that to be a human being means to be by nature pugnacious, curious, subject to fatigue, responsive to praise and blame, etc., and susceptible to training in all these respects. By virtue of the fact that we are all members of the human race, we have common characteristics; by virtue that we are individuals, we all display specific variations in specific human capacities. There is, save abstractly, no such thing as a standard human being. We may intellectually set up a norm or standard, but it will be a norm or standard from which every individual is bound to vary.
The fact that individuals do differ, and in specific and definable respects, has most serious consequences for social life. It means, briefly, that while general inferences may be drawn from wide and accurate observations of the workings of human nature, these inferences remain general and tentative, and if taken as rigid rules are sure to be misleading. Theories of education and social reform certainly gain from the general laws that can be formulated about original human traits, fatigue, memory, learning capacity, and the like. But they must, if they are to be applicable, take account also, in a precise and systematic way, of the variety of men's interests and capacities. To this fact of variety in the original nature of different men social institutions and educational methods must be adapted. Arbitrary rules that apply to human nature in general do not apply to the specific cases and specific types of talent and desires. Educational and social organizations can mould these, but the result of these environmental influences will vary with individual differences in original capacities. We can waste an enormous amount of time and energy trying to train a person without mechanical or mathematical gifts to be an engineer. We not only save energy and time, but promote happiness, if we can train individuals so that their specific gifts will be capitalized at one hundred per cent. They will be at once more useful to society and more content with themselves, when they are using to the full their own capacities. They will at once be unproductive and unhappy when they find themselves in activities or social situations where their genuine talents are given no opportunity and where their defects put them at a conspicuous handicap.
Individuals differ, it must further be noted, not only in specific traits, but in that complex of traits which is commonly called "intelligence." In the broadest terms, we mean by an individual's intelligence his competence and facility in dealing with his environment, physical, social, and intellectual. This competence and facility, in so far as it is a native endowment, consists of a number of traits present in a more or less high degree, traits, for example, such as curiosity, flexibility of native and acquired reactions, sociability, sympathy, and the like. In a sense an individual possesses not a single intelligence, but many, as many as there are types of activity in which he engages. But one may classify intelligence under three heads, as does Thorndike:[1] mechanical intelligence, involved in dealing with things; social intelligence, involved in dealing with other persons; and abstract intelligence, involved in dealing with the relations between ideas. Each of these types of intelligence involves the presence in a high degree of a group of different traits. Thus, in social intelligence, a high degree of sympathy, sensitivity to praise and blame, leadership, and the like, are more requisite than they are for intelligent behavior in the realm of mechanical operations or of mathematical theory. A person may be highly intelligent in one of these three spheres and mentally helpless in the others. Thus, a brilliant philosopher may be nonplused by a stalled motor; a successful executive may be a babe in the realm of abstract ideas. But what we rate as a person's general intelligence is a kind of average struck between his various competences, an estimate of his general ability to control himself in the miscellaneous variety of situations of which his experience consists.
[Footnote 1: "Measuring Intelligence," Harper's Magazine, March, 1920.]
There have been a number of tests devised for the purpose of estimating an individual's general intelligence.[1] On a rating scale such as is used in these examinations most individuals will come up to a certain standard that may be called average or normal. There will be a certain number so far below the normal rating in a complex of traits that go to produce intelligent (competent and facile) behavior that they will have to be classed as subnormal, ranging from feeblemindedness to idiocy. A certain number will be found so extraordinarily gifted in general traits and in specific abilities—in given subject-matters, as, for example, in mathematics and music—that they will be marked out as geniuses. Following the laws of probability, the greater the inferiority or superiority, the more exceptional it will be.
[Footnote 1: These, in large part, deal with words and ideas and are, therefore, weighted in favor of abstract intelligence, and put at a discount individuals whose experience and whose intelligence are predominantly social or mechanical in character. Some of the tests are fairly adequate for mechanical intelligence, but no good tests have been devised for social intelligence. These tests, however, as used in the army and for appraising college entrants, as at Columbia University, have been demonstrated to be fairly good indices of general intelligence.]
Individual differences are, therefore, seen to be not simply differences with respect to given mental traits, but differences with respect to general mental capacity. Experimental investigation points to a graded difference in mental capacity, ranging from idiocy to genius, the largest group being normal or average, the size of the group diminishing with further deviation from the average in either direction.