According to this https://www.quora.com/Why-did-Dijkstra-say-that-%E2%80%9CObj... the quote was spoken to Bob Crawford in 1988 or so and appeared in the journal TUG LINES produced by the Turbo user's group, Issue 32 (August September 1989). Bob Crawford is alive, I presume one could ask him but I would rather not even link his faculty page because I am afraid he will be inundated by an avalanche of HN readers.