At a bare minimum, understanding entails being able to detect an internal contradiction: a paradox.

Your second ducat, like your second million, is never quite as sweet.

Use "entropy" and you can never lose a debate, von Neumann told Shannon - because no one really knows what "entropy" is.

Samuelson, however, hedged his personal bets - by putting some of his own money in Berkshire Hathaway.

Samuelson spotted a mistake in Bacheliers work. Bachelier's model had failed to consider that stock prices cannot fall below zero.

In The Tricky Art of Co-Existing, Sandi Toksvig navigates life's little dilemmas with wit and not-so-common sense. You'll learn the strange history of common courtesy and the one true secret of social success: how to not drive everyone around you crazy.

Are there any mythical beasts which aren't simple pastiches of nature? Centaurs, minotaurs, unicorns, griffons, chimeras, sphinxes, manticores, and the like don't speak well for the human imagination. None is as novel as a kangaroo or starfish.