First, my credentials: I have been a Beatles fan in general, and a Paul fan in particular, for just about ever.

Ham & High: Paul McCartney, George Harrison, Ringo Starr, and John Lennon in A Hard Day's Night. Picture: Bruce and Martha KarshPaul McCartney, George Harrison, Ringo Starr, and John Lennon in A Hard Day's Night. Picture: Bruce and Martha Karsh (Image: Archant)

I am one of the millions for whom The Beatles form an inextricable part of our lives and histories… rather like the Queen.

So I’ve read acres about them, never really tiring of it, no matter how familiar. But here is the thing about hefty biographies (and Lord, is this hefty – nearly 900 pages): they are never going to be bought and read by those with no more than a mild curiosity.

These doorstoppers are for the hard-core recidivists, the inveterate junkies who just can’t help it.

But of course one is craving eye-openers – new stuff to keep the pages turning – and you need have no fear of boredom or crushing deja-vu when Philip Norman is around: this Hampstead author is a real pro, who comes with considerable form… the nature of which actually makes it very surprising that Paul was even cooperative.

This biography is not ‘authorised’ – i.e the subject has input and editorial veto – but it is ‘approved’: Paul has not interfered with Norman talking to whomever he chose.

The reason that this is surprising (and no one was more surprised than Norman himself) is because in his monumental biography of John Lennon, Paul emerges very badly.

And Norman’s earlier book about The Beatles called Shout!, Paul always referred to as Shite! Over the decades there have been probably thousands of books about The Beatles, I am not kidding.

The best of them is the first volume (two more to come) of Mark Lewisohn’s massive and definitive history – and, very dispiritingly, both that and Norman’s McCartney are white and shiny and thick and ugly with horrible covers and typography.

Beautiful Paul took very few poor photographs, but Norman has found one, and I wonder why.

The huge strength of this biography is that while all other books on Paul more or less give up on him after The Beatles, Norman steams on for a further 450 pages – Wings, solo work, private life (sort of) and three marriages (the first and current rather more successful than the piggy in the middle).

The opening third of the book reads as a Beatles story, as how could it not? But during this and way beyond into Paul’s subsequent life there are many revelations.

He got a girl pregnant when he was just seventeen (you know what I mean): he was going to marry her, but she miscarried, and they drifted apart.

There have been very many threatened paternity suits down the decades – none of them proved, though in 1964 Brian Epstein did pay off one girl with £5,000.

The Fabs first tried drugs in Hamburg: Preludin (slimming pills) and chewing the wicks of Vicks Inhalers (Benzedrine). Epstein was in love with John (some say there was a brief affair) but never fancied pretty Paul McCartney was a DIY fan …!

Carpentry, painting, masonry: who knew? It was he who first turned on Mick Jagger to drugs. The farm on the Mull of Kintyre was bought not for Linda, but Jane Asher, many years before.

He grew his Sgt Pepper moustache not as a fashion thing but to cover a scar on his upper lip incurred when he fell off a moped.

The real surname of Linda Eastman – a true rock star groupie – was Epstein!

When he was engaged to her, Paul retained three other long term girlfriends, one of whom was living with him in Cavendish Avenue, St John’s Wood, a house he still owns after fifty years.

The garden there once had four horses in it (Linda, of course) and a geodesic dome containing a circular bed once owned by Groucho Marx. On and on.

Norman is a careful and very professional biographer: when the need arises for criticism to be made (and there is a fair bit) he quotes the detrimental views and negativity of others.

And at the end of this colossal book, what are we left with? Who is Paul McCartney?

Well … indisputably a musical genius, as well as a very kind, polite, thoughtful, funny, intelligent and thoroughly sane man … who can be mean and wildly generous, vain and self-deprecating, moderate and spontaneously excessive, modest and demanding, wholly aware of his incomparable achievements, and yet still to this day locked in rivalry with his greatest friend ever, John Lennon. ‘‘He died a legend,’’ Paul said once, ‘‘and I’m going to die an old man. Typical John!’’.

I was frustrated to find no mention of Paul’s later tastes in films, books, food, clothes, drink… and why, a few years ago, he sold his beloved Aston Martin DB5 which he had owned since 1965.

For the money…? Hardly: his worth now approaches a billion.

The book is an easy pleasure to read, and yet… it didn’t excite me. In the end, I was missing the wonder I always receive from McCartney’s music: that sheer, thrilling sense of joy.

Paul McCartney by Philip Norman published by Weidenfeld & Nicholson £25