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.
And there you have it, the meaning of life. At first, it's all just arbitrary, chosen at random by a guy staring out the window, who types something out because he thinks it'll do, whatever it is. But when the choice is made and the thing is decided to be whatever it is, it takes on its role and purpose, and before long we attach a meaning to it that is metaphysical and sublime. And then it seems like it was always supposed to be that way.
The number 42, which was picked out of thin air by Douglas Adams one day, can now be found all over the place, in books, band names, TV shows and software, as a symbol for fundamental truth. A guy in Minnesota had his name legally changed to Geoff Fourtytwo in 1998 (he beat me to it, the son-of-a-bitch). Like the day you were born, it was really just sheer chance, but it now stands for something profound.
I am fourty-two, so I am enlightened. I know all of the secrets. Can't you tell?