Voltaire rejected Gottfried Leibniz's philosophy of optimism - the idea that this world is the best of all possible worlds. In Candide, Voltaire satirizes Leibniz's views through the naive protagonist Candide, who experiences much suffering but still believes this is the best of worlds. Through Candide's travels across Europe and South America, Voltaire critiques social institutions and highlights man's inhumanity to man, showing the flaws in believing all is for the best.