THE PROBLEM OF THE BIRTH SUPPLY
that in nine cases out of ten you had simply produced mediocre offspring or offspring below mediocrity. Out of the remaining tenth a great majority would be beautiful simply by "taking after" one or other parent, simply through the predominance, the prepotency, of one parent over the other, a thing that might have happened equally well if the other parent was plain. The first sort of beauty (in my three formulæ) wedding the third sort of beauty, might simply result in a rather ugly excess of F, and again the first sort might result from a combination of
a, b, c, d, e, F, etc.,
and
A, b, c, d, e, f, etc.,
neither of which arrangements, very conceivably, may be beautiful at all when it is taken alone. In this respect, at any rate, personal value and reproductive value may be two entirely different things.
Now what the elements of personal aspect really are, what these elements a, b, c, d, e, f, etc., may be, we do not know with any sort of exactness. Possibly height, weight, presence of dark pigment in the hair, whiteness of skin, presence of hair upon the body, are simple elements in inheritance that will follow Galton's arithmetical treatment of heredity with some exactness. But we are not even sure of that. The height of one particular person may be due to an exceptional length of leg and neck, of another to an abnormal length of the vertebral bodies of the backbone; the former may have a rather less than ordinary backbone, the latter a stunted type of limb,
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