The practical truth, in all such cases, is that what we are to regard as the cause, if we are to single out any one, is not an absolute matter but relative to the special situation we have to meet. We are justified in selecting any factor which we may hope to control and thus bring about improvement, as the cause for the purpose in hand. If we are discussing eugenic marriage it may be quite proper to say that non-eugenic marriages are the cause of sixty per cent of insanity, provided we can show a probability that this per cent might be eliminated through the control of marriage. At the same time it might be true that sixty per cent could be eliminated by abolishing alcohol and venereal disease, and, again, that sixty per cent might be saved through better education and training—notwithstanding the fact that these three sixties added together are more than the total number of cases. To a great extent these are alternative methods of treatment, any one of which might be effective. It is on the same principle that a man who is suffering from illness brought on by heavy eating, lack of exercise, and hereditary weakness of the digestive organs, might be cured either by less food or more exercise, or, if it were practicable, by getting a better hereditary outfit. I do not mean to depreciate the statistical study of degeneracy, believing it to be of the utmost value, but its legitimate purpose I take to be to contribute authentic details which the mind can use, along with other facts, to help in forming a true picture of the social process leading up to the condition we are interested in. The particular facts and relations we get in this way are like the detailed studies a landscape-painter makes of trunks of trees, leaves, rocks, and water surfaces, which cannot be put directly into his painting, but which give him a perception of details by the aid of which his constructive vision can produce the whole which he strives to depict. The understanding of a social situation is always such a creative or artistic working of the mind and never a reproduction of statistics as such. I have before me the report of an investigation of the feeble-minded in a certain State, which contains carefully prepared tables and diagrams showing the number and grade of the mentally defective, their sex, age, nativity, ancestry, school progress, delinquency, physical condition, and many other pertinent facts. Such a report is of great value to a capable mind which already has a sound general understanding of the subject, and of its relation to other subjects, but in the lack of these it is of little or no use; it is a raw material which needs a trained imagination to give it form and meaning. If there is any kind of knowledge for which a highly specialized action of the mind suffices, it is not sociology, which always calls for a large synthesis of life.