It’s one of the band’s loveliest songs (heightened by a sped-up piano bridge that sounds like a harpsichord), and also one of the most disputed in terms of authorship. Lennon claims he wrote the melody, but McCartney recalls sitting down with his bandmate’s lyrics at a Mellotron and crafting the tune with inspiration from The Miracles. It certainly sounds more Lennon-ish (he sings it after all), but it has a sentimental quality that suggests there was at least some input from McCartney. That’s what makes it their best song. Regardless of who wrote the music, it sounds like a true, 50-50 collaboration. It’s Lennon-McCartney at the peak of their song craft.

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