I started reading A Wicked Company: The Forgotten Radicalism of the European Enlightenment by Philipp Blom. Blom asks why Voltaire and Rousseau are buried in the Pantheon while Holbach and Diderot are in unmarked graves in a rural church whose priest won't even acknowledge their existence. The book is a celebration of the Radical Enlightenment, particularly Holbach's salon. Unlike other nonbelievers who replicate the life-denying morality of Christianity. Holbach and Diderot, says the author, valorize pleasure and the affirmation of life in a meaningless universe.
Don't take my word for it. Here is the publisher's blurb:
The flourishing of radical philosophy in Baron Thierry Holbach's Paris salon from the 1750s to the 1770s stands as a seminal event in Western history. Holbach's house was an international epicenter of revolutionary ideas and intellectual daring, bringing together such original minds as Denis Diderot, Laurence Sterne, David Hume, Adam Smith, Ferdinando Galiani, Horace Walpole, Benjamin Franklin, Guillaume Raynal, and Jean-Jacques Rousseau.
In A Wicked Company, acclaimed historian Philipp Blom retraces the fortunes of this exceptional group of friends. All brilliant minds, full of wit, courage, and insight, their thinking created a different and radical French Enlightenment based on atheism, passion, reason, and truly humanist thinking. A startlingly relevant work of narrative history, A Wicked Company forces us to confront with new eyes the foundational debates about modern society and its future.