To Charles Kingsley   6 November [1867]¹

My dear M^r. Kingsley

The subject to which you refer is quite new to me & very curious. I had no idea that the double function of an excretory passage had ever played a part in the history of religion.² I agree with what you say on speciality of organs being the best proof of highness in the scale of beings; nevertheless, when man as a standard of comparison is excluded, as with plants, it seems to be nearly impossible to give a good definition of Highness.³ I do not feel sure that a passage performing a double function, if performed well, ought to be considered as a sign of lowness. I suppose that the presence of rudiments must be looked at as an imperfection, but it seems very doubtful whether these records of a former, & in most cases lower, state should be viewed as indices of relative lowness in the scale. Some authors, indeed, have used them as proofs of an opposite position.— It is an extraordinary fact that even Man should still bear about his body the plain evidence, as it seems to me, of the former hermaphrodite condition of the parent-form of all the Vertebrata.—⁴

From what you formerly wrote, I had hoped to have seen a review by you on the Reign of Law, but I have not been able to hear of its appearance.⁵

Pray believe me | Yours very sincerely | Charles Darwin