It has been a week since Paul McCartney celebrated his 80th birthday, and on Saturday he will play to a huge crowd at the festival. The surge of reminiscence and celebration these two events have triggered has felt like a rerouting of some of the feelings the public were encouraged to project on to the Queen's Platinum Jubilee.

In contrast to flags, pageantry and a final connection to the second world war, McCartney's big week has been all about the popular culture that he and the Beatles helped create in the 1960s. These things are important in times of uncertainty and acrimoniousness.

The view of McCartney has changed over time. The idea that John Lennon was better than anyone else has given way to an accurate appreciation of the two of them. The best of the music he made after the Beatles broke up is now seen as rich, exploratory stuff that influenced later generations of musicians. McCartney's way of living has set an example to other superstars and the rest of us. He and his wife made sure that their children attended state schools. They were early adopters of vegetarianism. On past tours, he has made a point of being briskly tutored in the language of whichever country he finds himself, in order to get closer to communicating meaningfully with his audience.

To reduce his vast body of work to an essential idea or principle is ridiculous. One theme runs through his life and work. In Get Back, the acclaimed three-part documentary series that the director Peter Jackson edited from hours of Beatles footage filmed in early 1969 McCartney is shown as a sensitive, worldly man with a level of emotional literacy that was rare back then.

In keeping with these qualities, there is something he has always understood as a matter of instinct: that his messages enrich their lives and his.