St. Augustine:

"Do you wish to be great? Then begin by being. Do you desire to construct a vast and lofty fabric? Think first about the foundations of humility. The higher your structure is to be, the deeper must be its foundation."

Voltaire On Philosophy

“When he who hears does not know what he who speaks means, and when he who speaks does not know what he himself means, that is philosophy”

Thales Quote:

"Nothing is more active than thought, for it travels over the universe, and nothing is stronger than necessity for all must submit to it."