Most of Leibniz's philosophical writings are occasional pieces, addressed to various people. The two published in his lifetime were Essais de Théodicée sur la bonté de Dieu, la liberté de l'homme, et l'origine du mal (1710) and Monadology (1714). It was largely these works that influenced Christian von Wolff, whose popularization of the Leibnizian system became the standard academic philosophy in 18th-century Germany.
Leibniz's major philosophical work, Nouveaux Essais sur l'entendement humain (1704), contains the views of Leibniz on points raised in Locke's Essay Concerning Human Understanding. Because of Locke's death, however, it was not published until 1765. The publication of Nouveaux Essais in 1765 was important because it revealed for the first time the "true Leibniz" as opposed to the popularized version of Wolff, and it had a decisive effect on Immanuel Kant and the whole German Enlightenment.