IN FRIEDRICH SCHLEGEL'S Philosophie der Geschichte of 1829 there is a remarkable notion about the Enlightenment and Islam. According to Schlegel, the origins of pure monotheism, which the prophet of Islam claims to have reestablished, are arguably not to be found with the patriarchs of the Old Testament, but in the philosophy of the eighteenth century, “besonders der ganz seichten und oberflächlichen” Had this philosophy been earnest and consistent, it should have had the courage “den Mahomet wenn auch nicht als Propheten, doch wenigstens als den wahren Reformator der Menschheit und des Glaubens, den ersten Verkünder und großen Lehrer der reinen Wahrheit, und den eigentlichen Stifter der geläuterten Vernunftreligion laut anzuerkennen und öffentlich zu verehren.” In an explanatory footnote Schlegel names two exponents of this inconsistent philosophy and their works: Lessing's Nathan and Voltaire's Mahomet. While the mention of Mahomet ou le fanatisme (1740) is surprising, since the prophet of Islam appears anything but a teacher of a reasonable religion, the reference to Nathan der Weise (1779) was predictable.

The notion that the Enlightenment changed the European attitude towards Islam in a positive way, approaching the other religion and culture with tolerance or even appreciation, is fairly common. As the citation of Schlegel indicates, this attitude probably goes back to before the nineteenth century. There is definitely a change in the perception of Islam compared to the Middle Ages and the Early Modern Period characterized by its confessional conflicts.