Disagreement and Respect
Darwin rarely engaged with critics publically. Letters exchanged with Adam Sedgwick, professor of geology at Cambridge, and Richard Owen, the eminent comparative anatomist, show how Darwin tried to manage strong disagreement in the more private realm of correspondence. In the case of Sedgwick, Darwin was able to remain on friendly and respectful terms with his former professor. In the case of Owen, however, though their theoretical differences were less severe, the relationship quickly deteriorated and Darwin came to regard him as a bitter enemy.
Darwin and Sedgwick
Letter 2525 — Darwin, C. R. to Sedgwick, Adam, 11 Nov 1859
Darwin writes to Sedgwick to tell him that he has contacted his publisher John Murray to send him a copy of Origin. Darwin’s conclusion is diametrically opposed to that which Sedgwick has often advocated, but he assures Sedgwick he does not send his book out of a spirit of bravado, but a want of respect.
Letter 2548 — Sedgwick, Adam to Darwin, C. R., 24 Nov 1859
Adam Sedgwick thanks Darwin for the Origin. Sedgwick has read the book “with more pain than pleasure”. He says Darwin has deserted “the true method of induction” and many of his wide conclusions are “based upon assumptions which can neither be proved nor disproved”. He says that Darwin’s “grand principle natural selection” is “but a secondary consequence of supposed, or known, primary facts” He ends by saying he writes in the spirit of brotherly love and as his true-hearted friend.
Letter 2555 — Darwin, C. R. to Sedgwick, Adam, 26 Nov 
Darwin says Sedgwick could not have paid him a more honourable compliment than expressing freely his “strong disapprobation” of his book. He is grieved “to have shocked a man whom I sincerely honour”. He mentions that he has worked “like a slave” on the subject for over 20 years and is not conscious that bad motives have influenced the conclusions at which he has arrived. Darwin does not think the book will be mischievous and states: “if I be wrong I shall soon be annihilated”. Darwin may have written too confidently from feeling confident that no “false theory would explain so many classes of facts”.
Darwin and Owen
Letter 2526 — Owen, Richard to Darwin, C. R., 12 Nov 1859
Owen says to Darwin he will welcome his work [Origin] with a “close & continuous perusal”. He believes in the “operation of existing influences or causes in the ordained becoming and incoming of living species” and so could not regard Darwin’s attempt to demonstrate the nature of such influences as “heterodox”.
Letter 2575 — Darwin, C. R. to Lyell, Charles, [10 Dec 1859]
Darwin discusses with King’s College, London Professor of geology, Charles Lyell at length a conversation with Owen concerning Origin. Darwin notes “that at bottom he goes immense way with us”, but emphasises Owen’s unfriendly manner. Darwin remarks that Owen accepted a relationship between bears and whales: “By Jove I believe he thinks a sort of Bear was the grandpapa of Whales!” Darwin has heard Herschel considered his book “the law of higgledy-piggledy”.
Letter 2580 — Darwin, C. R. to Owen, Richard, 13 Dec 
Darwin responds to Owen’s remarks that his book [Origin] is not likely to be true because it attempts to explain so much. Darwin describes how, for fear this might be so, he resolved to give up the work if he could not convince two or three competent judges. He is sensitive because of “unjust things” said by a “very distinguished friend” [A. Sedgwick]. Value of his views now depends on men eminent in science.
Letter 2767 — Darwin, C. R. to Gray, Asa, 25 Apr 
Darwin discusses Origin reviews with Harvard botanist Asa Gray. Darwin is annoyed at Owen’s malignity [Edinburgh Rev.111 (1860): 487–532].