TO BE LIBERAL IS TO BE SANE.

1.
favorable to or in accord with concepts of maximum individual freedom possible, esp. as guaranteed by law and secured by governmental protection of civil liberties.
2.
favoring or permitting freedom of action, esp. with respect to matters of personal belief or expression: a liberal policy toward dissident artists and writers.
3.
of or pertaining to representational forms of government rather than aristocracies and monarchies.
4.
free from prejudice or bigotry; tolerant: a liberal attitude toward foreigners.
5.
open-minded or tolerant, esp. free of or not bound by traditional or conventional ideas, values, etc.