
“Basic research is what I am doing when I don't know what I am doing.”
In an interview in the New York Times (16 December 1957), cited in a footnote on page 32 of "Work, Society, and Culture" by Yves Reni Marie Simon, and also in a footnote (in German) on page 360 of "Vita activa oder Vom taetigen Leben" by Hannah Arend (1981)
Variants:
Basic research is when I'm doing what I don't know I'm doing.
Research is what I'm doing when I don't know what I'm doing.
Basic research is what I am doing when I don't know what I am doing.