“The answer to this is very simple. It was a joke. It had to be a number, an ordinary, smallish number, and I chose that one. Binary representations, base thirteen, Tibetan monks are all complete nonsense. I sat at my desk, stared into the garden and thought '42 will do'. I typed it out. End of story.”

Adams described his choice as 'a completely ordinary number, a number not just divisible by two but also six and seven. In fact it's the sort of number that you could without any fear introduce to your parents'

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