On saying “I don’t know”

Those three little words — “I don’t know” — may be modern science’s most important contribution to the world. Yes, we have learned an astonishing amount about how the world works, but of equal significance is our growing awareness of how much we don’t know. The physician/essayist Lewis Thomas wrote: “The greatest of all the accomplishments of twentieth-century science has been the discovery of human ignorance.”
Charles Darwin was certainly not adverse to saying “I don’t know,” and did so frequently in his many letters to family and friends. He was especially ready to confess his ignorance with regard to the big questions, the questions traditionally addressed by religion. Like Einstein and other great scientific minds after him, he was deeply conscious of the profound mystery of existence, and reluctant to cover his ignorance with myth and fable.
Science Musings by Chet Raymo