Interesting, but only tantalizing. No clear answers. Was Darwin, like Jefferson, a philosophic ( though not religious) Christian? Was he fully agnostic? A reluctant atheist? A complete nonbeliever? We know he felt that if there was a God, He was beyond human comprehension, but did he believe at all? We still do not know.
"On the other (hand), I cannot anyhow be contented to view this wonderful universe, and especially the nature of man, and to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe what he can. Certainly I agree with you that my views are not at all necessarily atheistical."
Yes, not necessarily...but...What could you believe, Dr. Darwin? What were your hopes?