Who knows what depths lurk in a man

To look at you, one would think you were just an ordinary sort of amiable idiot - certifiable, perhaps, but quite harmless. Yet, in reality, you are a worse scourge than the Black Death. I tell you, Bertie, when I contemplate you I seem to come up against all the underlying sorrow and horror of life with such a thud that I feel as if I had walked into a lamp post.

(from Right Ho, Jeeves, by Sir Pelham Wodehouse)