Julian Simon privately admitted in an October 1989 letter that his 1980 wager win partly reflected luck, a year before the public payoff

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In October 1989 — roughly a year before the 1990 payoff of the Simon-Ehrlich wager — economist Julian Simon wrote to Paul Ehrlich, John Harte, and John Holdren conceding that the outcome, which he already expected to win, partly reflected luck rather than a settled economic law. Paul and Anne Ehrlich's 1996 book Betrayal of Science and Reason (Island Press, pp. 100–104) — excerpted on Ehrlich's own Stanford Center for Conservation Biology page — quotes the letter in an endnote: "Simon himself admitted he was lucky in a letter to Ehrlich, Harte, and Holdren in October 1989. Crowing in advance about his victory, he said, 'I have been lucky that this particular period coincided so nicely with my argument.'"

The source of the quote is doubly mediated — Simon's private words, preserved and relayed seven years later by the opponent he beat, in that opponent's own published book. That structure recurs elsewhere in this vault as a pattern worth flagging on its own terms (see the Song Jian self-credit case, claim-song-jian-self-credited-1980-projections-triggered-one-child-policy), though here the roles are reversed: it is the loser's framing of the winner's private admission, not a winner crediting himself. No independent copy of Simon's 1989 letter has been located; the claim rests on Ehrlich's transcription as the sole textual source.