42 is the Answer to the Ultimate Question of Life, the Universe and Everything. This Answer was first calculated by the supercomputer Deep Thought after seven and a half million years of thought. This shocking answer resulted in the construction of an even larger supercomputer, named Earth, which was tasked with determining what the question was in the first place.
The Earth was destroyed by the Vogons five minutes before its ten-million year program was due to be completed. One of the only two humans who had survived the destruction of Earth, namely Arthur Dent, pulls random Scrabble tiles from a bag. When his friend, Ford Prefect, lines up the tiles, they spell, 'What do you get when you multiply six by nine?' Some readers of Adams have thought that this question was the aforementioned Ultimate Question. After all, it is Arthur who has been led to reveal this answer; Arthur is indeed from Earth; the Earth was the giant computer built to work out exactly what the Ultimate Question was; and 'what is 6 x 9?' is a bona fide question.
However, the Golgafrinchans (or rather the useless third of their population) have arrived on Earth; and this has interfered with the Earth as program-to-determine-the-Ultimate-Question. Hence, 'What is six by nine?' is not the Ultimate Question; and, of course, anyway, 6 x 9 is 54, not 42. (6 x 9 is 42 in 13 base numeral system)
Behind the scenes
- Readers have speculated, though, that 6 x 9 does indeed equal 42 when one calculates in base 13. Adams responded thus: 'I may be a sorry case, but I don't write jokes in base 13.'
Inspiration for the number 42
There are quite a lot of numbers to choose from, so why did Douglas Adams choose 42? Basically he wanted a small, ordinary, innocuous number and he picked 42. This message from Adams explains his choice.
- This implementation of Deep Thought
- Chapters 3, 6 and 9 of Joll ed., Philosophy and The Hitchhiker's Guide to the Galaxy (Palgrave Macmillan, 2012).