Happily men don't realise how stupid they are, or half the world would commit suicide. Knowledge is a will-of-the-wisp, fluttering ever out of the traveller's reach; and a weary journey must be endured before it is even seen. It is only when a man knows a good deal that he discovers how unfathomable is his ignorance. The man who knows nothing is satisfied that there is nothing to know, consequently that he knows everything; and you may more easily persuade him that the moon is made of green cheese than that he is not omniscient.

Author: W. Somerset Maugham