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40 corpse of a courtier and dilettante like Samuel Rogers." It is only opinion for opinion. Nobody can pretend that either Mary Godwin or Samuel Rogers was mad; and the general view a man may hold about the healthiness of inheriting their blood or type is simply the same sort of general view by which men do marry for love or liking. There is no reason to suppose that Dr. Karl Pearson is any better judge of a bridegroom than the bridegroom is of a bride.

An objection may be anticipated here, but it is very easily answered. It may be said that we do, in fact, call in medical specialists to settle whether a man is mad; and that these specialists go by technical and even secret tests that cannot be known to the mass of men. It is obvious that this is true; it is equally obvious that it does not affect our argument. When we ask the doctor whether our grandfather is going mad, we still mean mad by our own common human definition. We mean, is he going to be a certain sort of person whom all men recognise when once he exists. That certain specialists can detect the approach of him, before he exists, does not alter the fact that it is of the practical and popular madman that we are talking, and of him alone. The doctor merely sees a certain fact potentially in the future, while we, with less information, can only see it in the present; but his fact is our fact and everybody's fact, or we should not bother about it at all. Here is no question of the doctor bringing an entirely new sort of person under coercion, as in the