Spies are of no use nowadays. Their profession is over. The newspapers do their work instead.

Secrets are rarely betrayed or discovered according to any program our fear has sketched out.

If you read somebody’s diary, you get what you deserve.

Secrecy lies at the very core of power.

The life of spies is to know, not be known.

There is a sickness among tyrants: they cannot trust their friends.

The first duty of a good inquisitor is to suspect especially those who seem sincere to him.

To know all is not to forgive all. It is to despise everybody.

There is nothing more deceptive than an obvious fact.

Even a paranoid can have enemies.

Guard more faithfully the secret which is confided to you than the money which is entrusted to your care.

For sooner will men hold fire in their mouths than keep a secret.

If the world were good for nothing else, it is a fine subject for speculation.