There is nothing makes a man suspect much, more than to know little.

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

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

Once suspicion is aroused, everything feeds it.

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

Even a paranoid can have enemies.

Three may keep a secret, if two of them are dead.