For my sins, a correspondent sends me John Tamny, writing in National Review on Ben Bernanke:

John Tamny on the Ben Bernanke and the Federal Reserve on NRO Financial : And to prove that Bernanke's output-gap inflation theories are long-held, as opposed to being one-time slips-of-the-tongue, various speeches and editorials over the years make clear that in his model, neither inflation nor deflation are monetary events.

Let's go to the videotape:

Ben Bernanke: Ultimately, inflation is a monetary phenomenon, as suggested by Milton Friedman's famous dictum.... [T]he expectational Phillips curve is fully consistent with inflation's being determined by monetary forces in the long run. This point, originally made by Friedman himself, has been demonstrated in many textbooks...