For readers in the History of Ideas, The Enlightenment is intellectual history of the highest order, with Peter Gay’s erudition clearly on display, and a bibliographical essay (taking up fully a quarter of the bound pages) to make you cry for all you will never have time to read.

The focus here is on the effort by the philosophes and their fellow travelers to overcome, as they saw it, the irrationality and superstitions of medieval Scholasticism. This is a well-known story of the 17th-18th c. European Enlightenment. What makes Gay’s book useful is the attention that he pays to the congruities between the brightest lights of Christian theology and the ‘enlightened’ thinkers. After a thorough examination of the Enlightenment sources (again, that delicious bibliography), Gay doubles back and uncovers the work of late-medieval churchmen who were writing exegetical critiques of the extant orthodoxies—and in so doing anticipated many of the attacks leveled against Scholasticism by the philosophes. Many of the churchmen were proto-scientists, motivated by the Christian view of rationality and inspired to investigate the natural world so as to better understand divine purpose. For a while, writes Gay, theology became philosophy, but the Reformation challenge provoked a reactionary retrenchment, and theologians largely abandoned rationality for myth. It was the elevation of ‘mere myth’ to the status of philosophy that riled up so many of the philosophes.

Peter Gay makes a strong case for understanding the European Enlightenment not as a sudden repudiation of medieval irrationality, but as a gradual evolution in western philosophy. And while the philosophes claimed ancestry among the Classical Greeks, there was a more immediate antecedent of which they were ignorant.