When it comes time to protecting the homeland, the United States of America must be right 100 percent of the time. And the enemy, which desires to strike us again, only has to be right once.
It is one of the great troubles of life that we cannot have any unmixed emotions. There is always something in our enemy that we like, and something in our sweetheart that we dislike.
There is no great harm in the theorist who makes up a new theory to fit a new event. But the theorist who starts with a false theory and then sees everything as making it come true is the most dangerous enemy of human reason.
The end and aim of spying in all its five varieties is knowledge of the enemy; and this knowledge can only be derived, in the first instance, from the converted spy. Hence it is essential that the converted spy be treated with the utmost liberality.
The most common cause of low prices is pessimism - some times pervasive, some times specific to a company or industry. We want to do business in such an environment, not because we like pessimism but because we like the prices it produces. It's optimism that is the enemy of the rational buyer.