Passages in your book... Greatly shocked my moral taste... There is a moral or metaphysical part of nature as well as a physical. A man who denies this is deep in the mire of folly. Tis the grown and glory of organic science that it does, thro' final cause, link material to moral; you have ignored this link; and, if I do not mistake your meaning, you have done your best in one or two pregnant cases to break it- were it possibly (which, thank God, it is not) to break it, humanity, in my mind, would suffer a damage that might brutalize it, and sink the human race into a lower grade of degradation that any into which it has fallen since its written records tell us of its history.
— Adam Sedgwick