Barry Miles wrote his authorized Biography of McCartney in 1998, based on hundreds of recorded interviews with McCartney, and although it is a bit spooky to read a biography about somebody who’s still alive and producing, this book is anecdotally interesting. Unfortunately the concentration on musical aspects in the book was a bit thin, but what can a writer know about playing bass guitar? At least Mr. Miles didn’t speculate too much about musical aspects…and McCartney graciously expounds upon his performing and his songwriting in the many entertaining interview excerpts which are included in the book.

photo credit: TheAlieness GiselaGiardino²³

Paul started playing guitar at the relatively late age of 14, compared to current children and current artists who start playing when they are 10 or even younger. When his mother passed away he concentrated his energy on music and obtained a Zenith acoustic guitar which he restrung for playing left handed. His father played piano by ear and despite his father’s expressed wish that Paul take proper Piano lessons, he taught himself piano, writing the tune for “When I’m Sixty Four” when he was 16 years old. Paul’s father worked in a music hall and heard the same song twice a night for a week. So Mr. McCartney brought this Vaudeville music home with him and also instructed the McCartney boys about identifying harmony. Paul attributes his ability to harmonize with John Lennon to lessons which he learned from his father. Paul’s grandfather played the “E-flat” bass and Paul’s father would point out the bass-lines on radio-songs to Paul during his childhood.
It was Paul McCartney who taught John Lennon how to tune his guitar, and it was he who taught John many guitar chords. Because Paul was left-handed and John right-handed, they could face each other with their guitar-necks at the same side, their fretboard-hands mirror-reflections of each other. This mirror-image of their fretboards meant that they were likely more focused and concentrated than, say, two right-handed or two left-handed guitarists would have been, having to look over to the opposite side of each fretboard to see the other. When writing a song, its useful to be able to look at one’s own fretboard, and when co-writing a song, it is very useful to have both fretboards close and within immediate visual range.
Fast-forward to the Beatles burgeoning career in Hamburg, Germany, in 1960, where their then bassist Stuart Sutcliffe decided to leave the Beatles. Paul had played his guitar until it broke, then played Piano as that instrument was on every music-hall stage. As he owned no instrument at all, it made logistical sense that Paul would man the newly vacated role of bass-player. In the early 60’s, a band would often have a rotating “lead vocals” role, and the Beatles were no exception. Even Ringo had at least one song on which he sang in every performance set-list and on every album. These songs were initially written by Lennon/McCartney, but towards the end of the Beatles’ career together it was Ringo who would write songs his own songs himself.
Back to Paul McCartney, one of his first “biggies”, one of his first solo-compositions which made it big was “All My Loving”, a song whose text was written first, and whose melody was subsequently written on piano. Paul was initially a guitarist (or more accurate, initially briefly a trumpeter and then a guitarist), and was early on fluent on the piano too, using it even to write songs from the age of 16 onwards.
Ringo Starkey joined the group at their recording producer’s insistence in 1962. Pete Best had a different attitude than the rest of the group, Ringo was a renown drummer in Liverpool and had filled in for Pete Best in Hamburg, and George Martin found that they needed a more convincing drummer for their studio work. I personally speculate that Ringo and Paul rhythmically clicked better than Pete and Paul because both Ringo and Paul are left-handed.
As mentioned, this creepily-titled biography, Many Years From Now, is rather sparse about Paul’s melody generation strategies. His lyrical authorship is however analyzed in detail. In the directly quoted interview excerpts, Paul divulges some details about his melodic wizardry:

Normally I write on guitar and have full chords, or on the piano and have full chords, but (“You won’t see me”) was written around two little notes, a very slim phrase, a two-note progression that I had very high on the first two strings of the guitar: the E and the B strings. I had it up on the high E position, and I just let the note on the B string descend a semitone at a time, and kept the top note the same, and against that I was playing a descending chromatic scale. Then I wrote the tune for “You won’t see me” against it. I changed it but it was still a two-note thing but instead of it going down I pushed it up and then came down again; just a slight variation. It was 100 per cent me as I recall, but I am always quite happy to give John a credit because there’s always a chance that on the session he might have said, “That’d be better.” To me, it was very Motown-flavored. It’s got a James Jamerson feel. He was the Motown bass player, he was fabulous, the guy who did all those great melodic bass lines. It was him, me, and Brian Wilson who were doing melodic bass lines at the time, all from completely different angles, LA, Detroit and London, all picking up on what each other did.

The book details the growing rivalry between composer/arranger/bassist Brian Wilson and the Beatles. Paul was particularly strong in his praise of the Beach Boys’ response to Rubber Soul – Pet Sounds – because Brian’s bass playing showed that the bass can weave its own melody around a chord, rather than just playing the root note of the chord.
Strangely enough, no mention of the title-phrase is made in the book, so the titling is a bit mysterious. Calling in at 655 pages, Many Years From Now is surprisingly bereft of songwriting strategies or performance anecdotes of any great utility to singing-bassists. This is a void which must be filled. A great many musicographies about Paul McCartney exist, but a Singing-Bassist Analysis on Paul McCartney is not yet existent.