Logical thought, power of appeal and tactfulness never fail to command attention and respect. It has always been thus, and it will unquestionably so remain. Many really able and brilliant men, however, lack balance and the faculty of calculation. They are too often swayed by emotions, and their intellectual powers, which otherwise might exert a controlling influence, are thus weakened, and often result in failure. True greatness in a man is gauged by what he accomplished in life, and the impress he left upon his fellow men. It does not consist of one act, of even of many, but rather their effort upon the times in which he lived, and how long they endure after the actor is gone from the throng of the living.
At the bar, in the pulpit, in the medical profession, and especially in political life, tact is the sine qua non to highest degree of individual success.
The Writings of Thomas Jefferson
Insight Unsolicited 