Listen to Paul McCartney on NPR's "All Things" podcast

Paul discusses the craft of songwriting and his new Pure McCartney best-of collection.

Listen here.

"If I was to sit down and write a song, now, I'd use my usual method: I'd either sit down with a guitar or at the piano and just look for melodies, chord shapes, musical phrases, some words, a thought just to get started with. And then I just sit with it to work it out, like I'm writing an essay or doing a crossword puzzle. That's the system I've always used, that John [Lennon] and I started with. I've really never found a better system and that system is just playing the guitar and looking for something that suggests a melody and perhaps some words if you're lucky. Then I just fiddle around with that and try and follow the trail, try and follow where it appears to be leading me. And sometimes it leads me down a blind alley so I have to retrace my steps and start again down another road.

"But I'm of the school of the instinctive. I once worked with Allen Ginsberg and Allen always used to say, 'First thought, best thought.' And then he would edit everything. But I think the theory is good. 'First thought, best thought.' It doesn't always work, but as a general idea I will try and do that and sometimes I come out with a puzzling set of words that I have no idea what I mean, and yet I've got to kind of make sense of it and follow the trail."