He'd be correct if he'd said we can discuss the subjects we think no one knows anything about. I wonder; did Feynman think no one knew anything about psychology?
The conversation took place in 1965; if Feynman believed that, as is likely, he was very probably correct. On the other hand, a lot of people probably thought they knew something about psychology; it was a popular subject at the time.
(Last month's started a little late, I thought I'd bring it back to its original schedule.)
A monthly thread for posting any interesting rationality-related quotes you've seen recently on the Internet, or had stored in your quotesfile for ages.