Aristotle was famous for knowing everything. He taught that the brain exists merely to cool the blood and is not involved in the process of thinking. This is true only of certain persons.
A citizen of America will cross the ocean to fight for democracy, but won't cross the street to vote in a national election.
My definition of a free society is a society where it is safe to be unpopular.
Adlai E. Stevenson Jr. (1900 - 1965), Speech in Detroit, 7 Oct. 1952
If a man will begin in certainties he shall end in doubts; but if he will be content to begin in doubts he shall end in certainties.
Sir Francis Bacon (1561 - 1626)