Joining Mr. Starr in his 70s next year will be the still-performing Bob Dylan ("May you stay forever young") and Paul Simon ("How terribly strange to be 70"). Following soon after will be Roger Daltrey ("Hope I die before I get old") and Mick Jagger, who is reported to have said, several grandchildren ago, "I'd rather be dead than singing 'Satisfaction' at 45."
A rock 'n' roll septuagenarian was someone the gerontologist Robert Butler could have only dreamed of in 1968, when he coined the term "ageism" to describe the way society discriminates against the old.
Dr. Butler, a psychiatrist, died, at age 83, a few days before Ringo's big bash. No one, his colleagues said, had done more to improve the image of aging in America. His work established that the old did not inevitably become senile, and that they could be productive, intellectually engaged, and active — sexually and otherwise. His life provided a good example: He worked until three days before his death from acute leukemia.
But as much as Dr. Butler would have cheered an aging Beatle onstage, his colleagues said he would have also cautioned against embracing the opposite stereotype — the idea that "aging successfully," in his phrase, means that you have to be banging on drums in front of thousands — or still be acting like you did at 22 or 42.
That stereotype is almost as enduring as ageism itself.
"The stories that we hear tend to pull us toward the extreme," said Anne Basting, the director of the Center on Age and Community at the University of Wisconsin at Milwaukee. "It's either the stories of young-onset Alzheimer's, or it's the sky-diving grandmas. We don't hear enough about the huge middle, which is the vast majority of folks."
In fact, for most people, the 70s represents the end, not a beginning. Life expectancy in this country is still 78 — higher for white women, lower for men and blacks. It is rising, but not as fast, perhaps, as our expectations. As Gloria Steinem said of her 70th birthday in 2004, "This one has the ring of mortality."
Yet with Clint Eastwood directing films at 80 and Betty White starring in a new sitcom at 88, the pressure for 70-year-olds is not to face mortality, but to kick up those slightly arthritic heels ever higher.
The eighth decade, said Dr. Basting, is "now seen as an active time of life: you're just past retirement, that's your time to explore and play mentally." But while many will be healthy, others will not. "There will be an increase in frailty and disability because people are living longer," said S. Jay Olshansky, a demographer at the University of Illinois at Chicago who studies aging. For some people, an increased risk of stroke and Alzheimer's "is going to be the price they pay for extended longevity," he said.
The risk, gerontologists say, is that in celebrating the remarkable stories, we make those not playing Radio City, and certainly those suffering the diseases that often accompany old age, feel inadequate.
Social policy may only contribute to that pressure. The European Commission recommended last week that European workers not be allowed to retire before 70, to keep state pension funds solvent. In this country, Representative John Boehner of Ohio, the Republicans' leader in the House, suggested raising the retirement age for Social Security benefits to 70 to keep the program afloat.
Thomas R. Cole, director of the McGovern Center for Health, Humanities and the Human Spirit at the University of Texas Health Science Center in Houston and the author of a cultural history of aging, said he hailed anyone who, borrowing a phrase from his mother, age 85, "is playing above the grass."
At the same time, he said, "if we don't pay attention to the dark side of our 70s and 80s, we're not going to pay enough attention to the people who need help."
"We're going to make it look like if you're sick, it's your own fault; if you're not having orgasms or running marathons, there's something wrong with you. We need to think carefully about how to take care of people who are frail. We need to allow people to not feel like failures when they can't do the things they used to do."
He traces the origins of this "splitting apart" of the reality of old age — good and bad — to the mid-1800s, when people in the United States first experienced what he calls "the legitimization of longevity."
Life expectancy was only 40, but people began to believe that humans could live to be old — which they defined as 80 or more.
"People first began to say, 'I'm here to live a long life, and if I work hard and am a good person and am middle class, I will die a good death,' " Dr. Cole said, " 'and if I don't do these things, I deserve a short life and a painful death.' "
That split persists, he said, in our obsession with health and longevity, visible to anyone glancing across a magazine stand.
"It assumes you can control these things through willpower," he said.
Gerontologists tend to think of successful aging as taking advantage of what potential there is, staying as socially and intellectually engaged as possible. Our culture tends to measure it more in terms of how active people are.
"It wouldn't do us a whole boatload of harm to reinstate some values to contemplation," said Dr. Basting. "Part of the pressure on older people to be successful and give back and volunteer and be active and play tennis is that we are a culture of doing. We don't really know how to be. That's something that late life gives us, is time to be. But that's stigmatized."
We might take a new model from musicians and other artists growing older. Creative types tend not to retire, but their later work often reflects their different stage of life. Dr. Cole cited the roles and films of Clint Eastwood, and the songs of Mr. Simon. "Old Friends" reflected on the strangeness of 70 from a young adult's perspective, but on an album released when he was 60, he sang of "growing old" from a first-person perspective.
On the other hand, Dr. Basting said, Mick Jagger might test the limits — can he really strut like that when he's 75?
For boomers, it can be particularly jarring to watch the icons of the rock 'n' roll era aging. Robert Kastenbaum, a 77-year-old psychologist who has written extensively on aging, compares it to a 50th high school reunion and meeting the girl you had a crush on.
"This bubble-headed girl who was too sexy to exist, there she is now as the most mature, sensible grandmother," he said. "You think you can't believe the difference. The fact is both of these things are true. She was truly adorable, now she is admirable."
We need to recognize all those stages, he said, and not think there is some dissonance. "It's tolerance of ambiguity."
Dr. Butler might have agreed. In a recording of what was apparently his last interview, conducted less than two weeks before he died, and posted on The New Old Age, the New York Times blog on aging, he told Joshua Tapper, "Sometimes the oldest person in the room comes up with the most thoughtful thing — not always.
"I think we ought to have a realistic portrait of all different periods of life and not try to romanticize old age as the most wonderful, all these great old wise people," he said. "I think that goes too far."
Does the pressure ever let up? Maybe.
Dr. Basting, who has studied elderly theater troupes, recalled that one member declared that the age of 90 was "true freedom."
"Anything you do, people are just shocked that you're alive," Dr. Basting said. "There's no expectations at 90."