thou art mortal

The books are to remind us what asses and fools we are. They're Caesar's praetorian guard, whispering as the parade roars down the avenue, 'Remember Caesar, thou art mortal.' Most of us can't rush around, talk to everyone, know all the cities of the world, we haven't time, money or that many friends. The things you're looking for, Montag, are in the world, but the only way the average chap will ever see ninety-nine per cent of them is in a book.

Fahrenheit 451 by Ray Bradbury