NEW YORK — Paul McCartney likes to get out of the Beatle bubble he’s lived in since he was 21 and just be a regular bloke. So he does. No disguises, no bodyguards. Just Paul.

Sometimes he goes bowling. Or grocery shopping. Or to the movies with his girlfriend and gets shushed by strangers for talking too much. A couple of years ago, he recalls, he found himself on a New York City bus. Or rather, New Yorkers found him on the bus.
Everyone stared as the famous passenger took his seat, but no one said a word. Finally, someone — “it was the African-American lady” — spoke up. “ ‘Hey!’ ” McCartney imitates, his delight at the memory evident. “ ‘Is you Paul McCartney?’ ”
“ ‘Yeah, I am!’ ” Sir Paul answered. “I’m in their face. I don’t shrink away. No point. I’m from Liverpool, you’ve just got to get with it.
“So I said, ‘Look, honey. Don’t shout across the bus. Come and sit here!’ ”
The woman accepted and the unlikely couple had a merry chat for several blocks. And then the world’s most celebrated songwriter reached his stop and melted into midtown Manhattan.
McCartney will play before 60,000-plus people at FedEx Field in Washington on Saturday, the third stop on his summer mini-tour and a milestone of sorts (the concert comes 45 years after the Beatles made their American concert debut in Washington, at the long-gone Coliseum). He’ll be surrounded by the usual rock-god trappings and airtight security. But he says he savors encounters like the one on the bus because they remind him of who he was before he and a few of his friends got together and revolutionized popular music.
“It grounds you, you know,” McCartney says. “It’s a balance thing. I’m just one of the people on the bus. I’m the famous one, but I’m behaving normally. ... Really, it’s important.”
McCartney is telling this story a few hours before a sold-out show at Citi Field, the gleaming new home of the New York Mets, ensconced in the ballpark’s visitor’s clubhouse. For an official senior citizen — impossibly, he’s now 67 — McCartney looks remarkably youthful. He’s slim, almost slight, and truth be told, could even stand a few more pounds. The famously cherubic face is fleshier and lined just enough to remind you that McCartney isn’t 21 anymore. The tousled hair is a flat brown. This is reassuring; who wants a Beatle, particularly the doe-eyed, ever-boyish Paul, to seem old or even to age at all?
The even better news is that McCartney’s voice remains strong and supple in his 50th year of performing. Critics generally applauded the vocals and writing on his last album, “Electric Arguments,” released last year under his Fireman alter ego. But McCartney is a revelation in concert. He plays straight through for about 2.5 hours each night, offering more than 30 tunes from his vast catalog. The set list ranges from such sweetly sung classics as “Blackbird” and the inevitable “Yesterday” to the frantic, voice-shredding chestnut “I’m Down.”
There are several nods to souls departed; “My Love” is dedicated to his late wife Linda, “Give Peace a Chance” goes out to John Lennon, and “Something” is sung in honor of its creator, George Harrison. McCartney plays the latter song on a ukulele that Harrison gave him.
McCartney says the emphasis on vintage is calculated to please. “It’s always difficult to do new songs,” he says. “You know, I look at myself and think, ‘OK, I’m coming to see this show, I’m just an ordinary audience member, what do I want to hear him do?’ And you know, a lot of it is hits. If I went to see Prince, I know the songs I want. I want ‘Purple Rain,’ please. You know if he doesn’t do it, someone says how was it and you have to answer, ‘Well, he didn’t do ‘Purple Rain.’ ... I don’t want (fans) to go home thinking ‘Oh, I would have liked to have heard ‘Hey Jude.’ ”
McCartney sees it as something akin to giving back to people the things that made them love him in the first place. “Oh, I want to do” the old songs, he says. “We made hits so people would like them. And so it’s gratifying that people do.”
As genial as McCartney is, interviewing him can be slightly disconcerting. His career has been so varied and rich that the potential questions are endless. What’s more, each time you look up, you’re conscious of a little out-of-body voice reminding you of just whom you’re sitting next to.
McCartney himself doesn’t seem all that impressed by his own legend. “The whole point about it, the Beatles, Wings and me now, is that I’m too busy living it to think about it or reminisce.”
Well, perhaps he can clear up at least one tiny mystery of several decades: What exactly is McCartney’s maddening lyric in “Live and Let Die”? Is it, “In this ever-changing world in which we live in”? Or “in which we’re living”?
McCartney seems genuinely puzzled. “Yeah, good question,” he says. “It’s kind of ambivalent, isn’t it? ... Um ... I think it’s ‘in which we’re living.”’
He starts to sing: “In this ever changing world. ... ’ It’s funny. There’s too many ‘ins.’ I’m not sure. I’d have to have actually look. I don’t think about the lyric when I sing it. I think it’s ‘in which we’re living.’ ‘In which we’re living.’ Or it could be ‘in which we live in.’ And that’s kind of, sort of, wronger but cuter. That’s kind of interesting. ‘In which we live in.’ In which we live in! I think it’s ‘In which we’re living.’ ”
Ah, thanks, mate. Clears things right up.
The larger mystery may be this: Why, after all these years, is he still showing up at all? After so much — the frenzied adulation of the Beatles years, the money and fame and personal tragedies, the tabloid divorce — what could he possibly want?
McCartney brightens at this. “I like what I do,” he answers instantly. “Also, I’m very darn lucky to get this job. I’ve had others that weren’t as good as this. Second man on a lorry — it was not the greatest job.
“And then you get the relationship with your audience, which sort of grows as you do shows. There’s great warmth there (and) it’s sort of healing. ... It’s what I wanted to do since I was a kid. Only now the amps are bigger.”
Including a well-received April performance at the Coachella Music Festival in April and a memorable appearance this month atop the Ed Sullivan Theater’s marquee on the David Letterman show, McCartney will play in only eight cities; the current tour winds up in three weeks.
The limited touring is a lifestyle choice. “My personal situation at the moment with my little 5-year-old daughter (Beatrice, with ex-wife Heather Mills) gives me certain periods of time when I can do what I want. Which is the strange thing about divorce. On the one hand, you become a single parent suddenly. But the upside of that is that it’s changed the way I tour now. So this, we call it Summer Live, is a little series of dates that are fitted in the gaps when I’m not being a dad. I love the balance. It’s really nice. The other few days, I go home and I’m dad, and when that period is over, I come back.”
He has thought about retirement, but not seriously and certainly not soon. “It’s what everyone else does, and that thought has to occur to you,” he says. “But strange things happen in music. You look at people like Tony Bennett, B.B. King — people who are as good if not better than they were. And you sort of think, oh! And you look at that as your beacon kind of thing. ... I certainly couldn’t just give it up like that. I like it too much.”
Which suggests that the once unimaginable is now not just possible but highly likely: a Beatle, rocking out at 70, even 75. Paul McCartney is almost there, and it doesn’t seem odd at all. In this ever-changing world in which we live in, it even seems kind of normal, like riding the bus.