"Second Dialogue", in: Three Dialogues on Knowledge, Oxford: Basil Blackwell, 1991. p.55.
Killing Time. Chicago – London: University of Chicago Press, 1995. p.174.
Quoted by Sheldon J. Reaven, "Time well spent", in J. Preston - G. Munévar - D. Lamb (eds),
The Worst Enemy of Science? New York - Oxford: Oxford University Press, 2000. p.26.