‘A favorite tradition was to attend Saturday midnight showings of “The Rocky Horror Picture Show” at the Key Theater on Wisconsin Avenue in Georgetown. … I didn’t dress up — sorry to disappoint you — but no party was complete until all of us danced “the Time Warp” to the movie’s famous song. As it happens, I still remember the steps, and I had intended to demonstrate “the Time Warp” for you, but that will not be possible today.’ 

It was a fine graduation speech on Sunday at Georgetown Law by the Fed chairman, Jerome Powell, even if one is hard pressed to divine any insights for monetary policy in his remarks. Feature the passage above recalling Mr. Powell’s own law school days in the late 1970s. By “Time Warp,” we wondered, could the head of America’s central bank be referring to the stagflation that characterized that era — and appears to be making a comeback?

Well, not quite. It turns out Mr. Powell was referencing a number from the genre-bending cult film of 1975, “The Rocky Horror Picture Show.” The chairman, tongue apparently in cheek, explained that “if you have led a culturally deprived life and are tragically unfamiliar” with the film, “it is a raucous musical starring a young Tim Curry.” Critic Roger Ebert once called it “one of those movies you have to use a lot of hyphens to explain.”

The film, as Amazon puts it, depicts “the travails of a squeaky clean couple stranded at a creepy castle” where the residents — under the leadership of a mad scientist, Dr. Frank N. Furter, played by Mr. Curry — “sing and dance through a bacchanalian romp of murder, bisexuality and cannibalism.” One could well find it hard to imagine William McChesney Martin or Alan Greenspan singing the praises of such a film — at least, not the cannibalism parts.

That’s not to say there’s anything objectionable per se in the Fed chairman regaling his listeners with pop culture recollections, no matter how outré. Mr. Powell, we take it, is a man of wide-ranging tastes. Last summer, he made something of a splash when he was photographed at a concert by a Grateful Dead spin-off group, Dead & Company. “It was terrific,” Mr. Powell said of the concert. “I’ve been a Grateful Dead fan for 50 years.”

When it comes to monetary policy, though, and the value of the dollar under the stewardship of the Fed, critics of the central bank could be forgiven for reflecting, “what a long strange trip it’s been,” to crib a phrase of the Grateful Dead. After all, measured in gold, the dollar has shed some 98 percent of its value since the creation of the central bank. Today, the Fed is having a hard time getting inflation down to its arbitrary, self-imposed target of 2 percent.

The mix of slowing growth alongside persistent inflation is raising the specter that plagued the economy in Mr. Powell’s law school days, stagflation. JPMorgan Chase’s Jamie Dimon warns it “is on the list of possible things” that could harm the economy. In 1975, stagflation led to an inflation rate above 10 percent. Unemployment reached 9 percent. In 1979, the year Mr. Powell graduated from Georgetown Law, Paul Volcker acceded to Fed chairman. 

Volcker was able to tame inflation with high interest rates, prompting fierce criticism after years of loose policies. He was aided by President Reagan’s supply-side fiscal and regulatory moves. The Fed now, though, appears to be flailing, first having trouble realizing inflation had taken root, and then surprised by its persistence. Mr. Powell may recall the moves to “the Time Warp,” but when it comes to fighting inflation, does the Fed still remember the steps?