One day in mid-October 1963, John Lennon had dropped by at the house in Wimpole Street, London, where Paul was living with the family of his girlfriend, Jane Asher.
The two of them went down to a little room in the basement and sat together on Mrs Asher’s piano stool.
Their manager Brian Epstein had told them that their next, most important task was to compose a song to crack the elusive American market.
Up to now, their hit singles in Britain — From Me To You, She Loves You, Please Please Me — had all flopped over there.
After an hour or so of doodling about, Paul went upstairs to the bedroom of Jane’s brother, and put his head around the door.
‘Do you want to come and hear something we’ve just written?’ he asked. Peter Asher accompanied him back downstairs, and together Paul and John played him their new song, I Want To Hold Your Hand.
‘What do you think?’ asked Paul. ‘Oh, my God! Can you play that again?’ said Peter. As he listened to it for a second time, he thought: ‘Am I losing my mind, or is this the greatest song I ever heard in my life?’