I'm a fan but hackles were raised early in Adam Gopnik's New Yorker piece, “The Forty-Year Itch,” about nostalgia and “Mad Men.” He writes that...

...it seems time to pronounce a rule about American popular culture: the Golden Forty-Year Rule. The prime site of nostalgia is always whatever happened, or is thought to have happened, in the decade between forty and fifty years past.

My immediate thought: Shouldn't that be the 20-year rule? In the 1960s, “Hogan's Heroes” and “Batman,” which was a satire of the 1949 serial “Batman & Robin,” “Happy Days” and “Grease” in the 1970s, and “That '70s Show” in the 1990s. The 20-year gap seems primed to allow for kids to grow up and attain a position of creative power, from which they render their childhood for everyone else. It allows the culture a period from which to grow up (or down), and miss (or disparage) what once was.

But Gopnik marshalls his 40-year arguments:

• 1940s: “Meet Me in St. Louis,” “The Magnificent Ambersons,” and “Take Me Out to the Ballgame,” all set during the first decade of the 20th century.
• 1950s: “The Seven Little Foys” and “A Night to Remember”: weak arguments.
• 1960s: Apparently there was a series called “The Roaring Twenties”? Musically, though, you had “Westminster Cathedral” and the '20s pastiche numbers of a Beatles-era Paul McCartney: “When I'm 64,” “Your Mother Should Know,” “Honey Pie,” etc. But that's Paulie more than the culture, isn't it? Please don't tell me, Adam, that your argument hinges on the oddities of little Paul McCartney.
• 1970s: “The Sting” and “Paper Moon” and... that's it. A better argument is “Star Wars,” which, though it took place a long ago, was like a compressed 1930s serial with better special effects. A better argument: “Annie” on Broadway.
• 1980s: “Raiders of the Lost Ark” (which Gopnik mistakenly places during World War II rather than 1936), “Hope and Glory,” “Empire of the Sun” and “Biloxi Blues.” But didn't the greater WWII-era nostalgia come about in the late '90s/early '00s with Brokaw's book, Spielberg's movie, and HBO's “Band of Brothers.” So is that the 50-to-60 year cycle?
• 1990s: a '50s-era love for Hush Puppies and Converse All-Stars? Plus skinny ties? I'm not feeling it. It wasn't like the greaser love we had in the blow-dried 1970s.

And that brings us to the '00s and “Mad Men.”

Further down, Gopnik admits that the 40-year nostalgia cyle...

...carries epicycles within it: the twenty-year cycle, for instance, by which the forty-somethings recall their teen-age years, producing in the seventies a smaller wave of fifties nostalgia to dance demurely alongside the longing for the thirties.

A smaller wave? From where I sat in the 1970s, which was generally on the floor watching TV as a teenager, the '50s boomed: “Happy Days,” “Grease,” Sha-Na-Na, and ultimately “Diner,” which was early '60s, but was released in the early '80s. Twenty-year cycle again.

The bigger point, which Gopnik doesn't delve into, is whether the 20-year or 40-year set piece is true nostalgia (a wish for a pristine, simpler time) or anti-nostalgia (mocking that earlier, dopier time). The first season of “Happy Days,” for example, never felt particularly happy to me. It was only later, with the rise of Fonzie, that the ostensible lead, Richie Cunningham, came out ahead at the end of each episode. Before that, the “Happy Days” title always felt a trifle ironic to me: an antidote for those who doted on the '50s.

“Mad Men” is even stronger in this regard. The show is advertised nostalgically (when men were men and women were curvy and more easily fondled) but presents such a horrific vision of chauvinism that even a semi-chauvinist like myself longs for women's lib to come along and right the damn ship. The show, beloved for its early '60s fashions, which are about to disappear in a haze of pot smoke and long hair and hippie, bearded naturalism, seems as much a comment on our times as its times. Think of that early scene when Sally Draper plays spaceman with the dry cleaner bag over her head and her mother warns that the clothes that were in that bag better be in good shape, young lady. Modern audiences laugh: “She's not concerned her daughter will suffocate!” At the same time, deep down, we know we're overconcerned. Back then, adults were adults and kids seemed unbreakable. Now there's something childish about us even as we treat our kids like fragile objects: carrying them from playdate to playdate.

In the end I think there's nothing golden about Gopnik's 40-year rule. And better to concentrate on what the nostalgic piece says about us. Do we think we're hipper now (which is how we got “Batman”), too complicated (which is why we needed “Happy Days”), without national purpose (thus “Greatest Generation”), or uptight (why we long for “Mad Men”)?

There's always something wrong with the present; there's always something good somewhere in the past.

“Mad Men”: Buttoned-up but revealiing our modern uptightness.