Gentlemen do not read each other's mail.
Source: Reason given for closing the Dept of State's code-breaking office; On Active Service in Peace and War, p.188, 1948.
-- Henry Lewis Stimson, (Sep 21 1867-1950), US government official; He exercised a strong influence on U.S. foreign policy in the 1930s and 1940s; served in the administrations of five presidents.