This post by Joe Carter on the history of atheistic philosophy is pretty good, mainly because he manages to quote Chesterton twice.

Where do the New Atheists get this silly notion that they are heirs of the Enlightenment? ... The rationalists of the Enlightenment era were able to trust in reason precisely because they were theists or deists and believed in a transcendent, rational God. To think otherwise was considered, as the philosophers often noted, the height of absurdity.