Vom Geist der Gesetze
During the period of Enlightenment in France, however, slavery and the trade of slaves were more and more criticized by philosophers of the Enlightenment. For instance, Montesquieu, in "The Spirit of the Laws" (1748) criticized those who called themselves Christians yet practiced slavery. Also, Voltaire, in "Candide" (1759), denounced the difficult conditions faced by African slaves. In 1788, Société des Amis Noirs ("Society of the Friends of the Blacks") was founded with the goal of abolishing the slave trade using the argument that slavery was in fact not economically profitable.