One of the many things that makes Rousseau so compelling is that, in the midst of a historical moment known for its elevation of reason, Rousseau embraced a series of non-philosophical, non-rational (not irrational) pathways to truth. Among the pathways to truth he embraced, Rousseau regarded reason as the least reliable. When properly constrained, reason could yield sublime truths, but, when exercised imperiously (as it ordinarily is), it leaves us less auspiciously positioned toward truth than we would be if we simply remained ignorant.1 Reason opens up sophisticated possibilities, but it obscures what Rousseau calls the “sublime science of simple souls”—the unmediated love of existence, common to human beings in our natural state. (DAS, iii:30; ii:22) Rousseau did preserve a space for what he called “simple” or “natural” reason in his system, assigning it a critical, if subsidiary, role in understanding the “truths that pertain to human happiness.” Simple or intuitive reason, when properly circumscribed and tied to sentiment, can serve truth, but discursive or philosophical reason is, in Rousseau’s view, almost always corrupting. While it may make “association agreeable,” reason contributes more often than not to a coarsening of morals. (E, iv:767; xiii:591)

Rousseau understood reason as a faculty that manifests itself only upon entry into society and develops only with the development of society. Reason is, then, not natural, but the potential for it is. It remains latent until society is born, at which point it manifests, never to be retracted. It is a potentiality, which, once activated, cannot be deactivated. Reason began, Rousseau believed, with comparison, or, perhaps more accurately, comparison was the impetus for the development of reason. Prior to entering society, human beings had not yet begun to make comparisons between themselves and others. However, once “the first person . . . fenced off a plot of ground” and said “this is mine,” (DI, iii:164; iii:43) the need for comparison developed, most obviously the distinction between “mine” and “not mine.” From mine and not mine were born a series of distinctions that fueled the development and proliferation of amour propre: distinctions between the beautiful and the ugly, between rich and poor, between high and low. From the selfsame faculty of comparison, however,

the distinction between right and wrong was also born-the origin of all systems of morality and foundation of moral philosophy. So, both morality and the source of its corruption-amour propre-were born out of comparison. Reason, then, is coeval with both the source of moral corruption and with morality itself.