Charles Darwin (1809–1882) British naturalist, author of "On the origin of species, by means of natural selection"
Letter to J.D. Hooker, 29 March 1863
In The Correspondence of Charles Darwin, volume 11, 1863; Frederick Burkhardt, Duncan Porter, Sheila Ann Dean, Jonathan R. Topham, Sarah Wilmot, editors; Cambridge University Press, September 1999, page 278
Sometimes paraphrased as “One might as well speculate about the origin of matter.”
Other letters, notebooks, journal articles, recollected statements