And if we wished to form sentiment from science, we should ask, which is the most reasonable, the most worthy, and the most consoling,--whether to believe that we alone are perfect, and that nine-tenths of our brethren who cover the globe are disinherited; or to consider all these varied existences which we see around us as forming equal, if not similar, species, pursuing, each in its own way, a destiny, different, indeed, but not degraded,--not degenerated,--in certain points even better arranged than our own. “God,” said Niebuhr, “has marked on each race of men their destination with the characteristic which best suits them” and the philosopher had already learnt by history that when civilisation has been suddenly introduced from without among a savage nation,[191] the consequence is an immediate physical degeneracy, that is to say, the destruction of the people which has wandered from its usual mode of life. The historian thus proclaimed a physiological law, which most monogenists are glad to forget,--that all degeneracy ends necessarily in death; it kills itself, and always at the tenth generation, if not at the first. No group of human beings, after two or three generations of unmixed existence, can be considered as degraded or degenerated, not more than we should admit that a young girl, attacked with cretinism in its greatest degree, had the characteristics of the Esquimaux or the Mongolian race.[192] We can see, even in a humanitarian point of view,--the point of view in which we refuse to place ourselves,--that the polygenists have the advantage. The mind is not offended, and cannot be so, to see certain creatures possess some particular faculty to the exclusion of others. Does not harmony obtain an absolute value from a necessary inequality of parts, whilst she herself restores to each part an equal value, in making them all co-operate towards the same end, the same _action_, in which are distributed great and minor parts,--some brilliant, some humble, some concealed?[193]