The only deadly sin I know is cynicism.
Henry Lewis Stimson (1867 - 1950)
Source: On Active Service in Peace and War, 1948, introduction
Contributed by: Zaady
The only way to make a man trustworthy is to trust him; and the surest way to make him untrustworthy is to distrust him and show your distrust.
Source: The Bomb and the Opportunity, March 1946