I am reading Frederick Hayek right now and saw that he refers to the French liberal tradition, what he calls French "individualism (vs the English liberal tradition of Smith, Ferguson, Burke, etc.) as the Cartesian school ("Individualism: True and False" in Individualism and Economics, pp. 6-8; Studies on the Abuse and Decline of Reason, pp. 52-54).
While I think I understand the general idea, was hoping to solicit some more detailed explanation. His seems to be the view that the French liberal tradition, which thought it could found a democratic society upon true and universal concepts of justice, got its faith in the power of abstract reason from Descartes. I suppose the link is that Descartes tried to find the immaterial laws of thought which were undoubtable.
But Descartes did not himself apply this to political phenomenon, besides perhaps in his Passions of the Soul, and other very general comments on the "moral sciences". The view seems to be that there was a chain of transmission through him to the philosophes which eventually became the French version of "individualism" that Hayek refers to. This chain if transmission I can read further into myself, but I was hoping to get some more detail about how the philosophes and those like them saw themselves as applying Descartes' theories on reasoning to political phenomena.