What to do if you find yourself stuck in a crack in the ground underneath a giant boulder you can't move, with no hope of rescue. Consider how lucky you are that life has been good to you so far. Alternatively, if life hasn't been good to you so far, which given your current circumstances seems more likely, consider how lucky you are that it won't be troubling you much longer.

Even light, which travels so fast it takes most races thousands of years to realize that it travels at all, takes time to journey between the stars.

I can see we're in for a fabulous evening's apocalypse.

If there's any real truth, it's that the entire multidimensional infinity of the Universe is almost certainly being run by a bunch of maniacs.

If on the other hand he went to pay his respects to The Door and it wasn't there . . . what then? The answer, of course, was very simple. He had a whole board of circuits for dealing with exactly this problem, in fact this was the very heart of his function. He would continue to believe in it whatever the facts turned out to be, what else was the meaning of Belief? The Door would still be there, even if the Door was not.

Trillian had come to suspect that the main reason [Zaphood] had had such a wild and successful life was that he never really understood the significance of anything he did.

Yes, it is true that sometimes unusually intelligent and sensitive children can appear to be stupid. But stupid children can sometimes appear to be stupid as well. I think that's something you might have to consider.