Any medical man who predicts exactly when a patient will die, or exactly how long he will live, is bound to make a fool of himself. The human factor is always incalculable. The weak have often unexpected powers of resistance, the strong sometimes succumb.

... obsessions are always dangerous.

There's nothing so dangerous for anyone who has something to hide as conversation.

Nothing, I believe, is so full of life under the microscope as a drop of water from a stagnant pool.

Evil never goes unpunished, Monsieur. But the punishment is sometimes secret.

What they need is a little immorality in their lives. Then they wouldn't be so busy looking for it in other people's.

Most successes are unhappy. That's why they are successes - they have to reassure themselves about themselves by achieving something that the world will notice.