Pierre Charron — French Philosopher

Pierre Charron was a French 16th-century Catholic theologian and philosopher, and a disciple and contemporary of Michel Montaigne... (wikipedia)

The most excellent and divine counsel, the best and most profitable advertisement of all others, but the least practiced, is to study and learn how to know ourselves. This is the foundation of wisdom and the highway to whatever is good.
The easiest way to be cheated is to believe yourself to be more cunning than others.
God, Nature, the wise, the world, preach man, exhort him both by word and deed to the study of himself.
Pleasure and pain, though directly opposite are contrived to be constant companions.
The true science and study of man is man.