This paper is only preliminary to the real object of my research. We have many books and articles on great men, their genius, their heredity, their insanity, their precocity, their versatility and the like, but, whether these are collections of anecdotes such as Professor Lombroso's or scientific investigations such as Dr. Galton's, they are lacking in exact and quantitative deductions. Admitting that genius is hereditary, or, what is more doubtful, that it is likely to be associated with insanity, we have only the 'yes' or 'no' as our answer. But this is only the beginning of science. Science asks how much? We can only answer when we have an objective series of observations, sufficient to eliminate chance errors, such as this list of a thousand preeminent men.
When we have such a series we can use what psychological insight we possess to classify our material. We can seek to distinguish genius from talent, and, having given these terms a more exact signification, can secure quantitative data regarding their relative frequency under varying conditions. We can determine how the man of unusual endowment in its various manifestations differs from his fellow men, both in those traits which distinguish him from them and in those traits which he shares with them. With traits that can be measured such as length of life, height, etc., we can readily compare the several classes of eminent men with other classes in the community. In the case of other traits, insanity for example, we must first determine its prevalence, according to a proper definition, in the various classes of eminent men and can then give a definite statement as to its relative frequency among them and a comparison with other classes. Other more intangible traits I am also endeavoring to measure. Qualities such as originality or kindliness are graded on a scale of eight, mistakes are eliminated by the numbers and we secure fairly reliable averages. The different classes of eminent men can then be compared inter se, and with other classes of the community, when the data for these are at hand. Then we have the distinctions on which I have already dwelt. We can only determine the causes of great men and their effects by a careful study of a number sufficiently large to eliminate accidental causes and errors in our estimate; but having done this, our results can be expressed in the definite measures of exact science.
In conclusion attention may be called to the practical importance of such determinations. Science must precede the applications of science. The father must discover the laws of the pendulum before the son can apply them to the clock. A Faraday and a Henry must investigate the phenomena of electricity before we can have the electric motor. It is evident that applications of psychology and sociology are not as yet numerous or important. But may not this be chiefly because the scientific principles are wanting? Education and government are carried
