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42 (h2g2, meaning of life, The Hitchhiker's Guide to the Galaxy)

Contributor(s): Josh Harmon, Peter Minearo and Mike Smith

In Douglas Adams' The Hitchhiker's Guide to the Galaxy, 42 is the number from which all meaning ("the meaning of life, the universe, and everything") could be derived.

A BBC radio script based on Adams' book contains the following lines:

("Cave man" lays out following sentence in Scrabble stones: "What do you get if you multiply six by nine?")
Arthur: Six by nine? Forty-two? You know, I've always felt that there was something fundamentally wrong with the Universe.
(Faint and distant voice:) Base thirteen!

For the literal-minded and those unfamiliar with terms like "base thirteen," this is a number system in which the number 10 is equivalent to our more familiar decimal 13. A base-13 number 42, therefore, is the same as four 13s plus 2, or decimal 54. So "six by nine" (six times nine) or decimal 54 is, in base 13, 42. For the mystically inclined, 42 in base 13 is the same as 101010 in binary (base 2). This could mean almost anything, and many Adams fans have spent untold hours discovering all of the places where the number "42" pops up. For example, there are many mentions of the number in the Book of Revelation. Others have made a game of finding 42s, such as these:

  • The angle at which light reflects off of water to create a rainbow is 42 degrees.
  • Two physical constants in the universe are the speed of light and the diameter of a proton. It takes light 10 to the minus 42nd power seconds to cross the diameter of a proton.
  • The sum of the ordinal alphabetic positions of the initials (SPG) for Stan (P.) Gibilisco, an oft-published science and technology writer, is equal to 42 (S=19, P=16, G=7).
  • A barrel holds 42 gallons.

(It should be noted that all of these 42s are base 10, not base 13.)

This was last updated in April 2007

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It is also the case that:
105 (base 8) is 69 (base 10),
105 (base 10) is 69 (base 16),
105 (base 16) is 69 (base 42).
42 in japanese translates to "shini" and "gami" put together as "shinigami" Meaning God of death.
"42" was a favorite number of Lewis Carroll - featured several times in the Alice books and "The Hunting of the Snark".  And Douglas Adams was an obvious fan of Carroll's work.  (He gave it away in his first version of h2g2 - naming the radio episodes by the archaic title "fits", borrowing from Carroll's use in The Hunting of the Snark.)

Especially important to h2g2's equation and "solution", the very first time Carroll hinted at his love of this number was when Alice was attempting to repeat her times tables (chapter two of Alice's Adventures in Wonderland) Her effort breaks down at 4 x 13 answered in base 42, which virtually reverses the failure of 'the Question' in h2g2, in that this one works when calculated in base 13.

In light of this, it is difficult to imagine that Adams was not drawing on Carroll  (and especially on the above chapter) in choosing and 'solving' for 42.



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