Adhesion to one idea is monomania; to few, slavery.
Galileo called doubt the father of invention; it is certainly the pioneer.
Courage enlarges, cowardice diminishes resources.
Economy is for the poor; the rich may dispense with it.
Most books fail, not so much from a want of ability in their authors, as from an absence in their productions of a thorough development of their ability.
Pure motives do not insure perfect results.