Temperance is a bridle of gold; he, who uses it rightly, is more like a god than a man.

Out of too much learning become mad.

Good science requires distinguishing between "felt knowledge" and knowledge arising out of testable observations. "I am sure" is a mental sensation, not a testable conclusion. Put hunches, gut feelings, and intuitions into the suggestion box. Let empiric methods shake out the good from bad suggestions.

One was never married, and that's his hell; another is, and that's his plague.

Good science is more than the mechanics of research and experimentation. Good science requires that scientists look inward-to contemplate the origin of their thoughts. The failures of science do not begin with flawed evidence or fumbled statistics; they begin with personal self-deception and an unjustified sense of knowing.

Our mental limitations prevent us from accepting our mental limitations.

Employment, which Galen calls 'Nature's Physician,' is so essential to human happiness that indolence is justly considered as the mother of misery.