Introduction

In Alan of Lille’s Plaint of Nature (De planctu Naturae), his leading speaker, Lady Natura, bases much of her argument against sin in general and homosexuality in particular on the claim that both amount to bad grammar. Researching that claim-its appeal to Alan and his audience, its literary use within his allegory, and its historical antecedents-is the germ of this project. What lies behind Natura’s claim, I believe, is a belief in a series of correspondences among several branches of philosophy: cosmology, ethics, and language theory. These correspondences echo the Stoics in ancient Greece and Rome, who divided their philosophical system into a similar triad: physics (including cosmology), ethics, and logic (including language theory and epistemology). Perhaps more importantly, the Stoics posited deep connections among these three branches, so that they were not considered in isolation of one another; further, they elaborated these connections with a systematic technical vocabulary. This system, and its supporting technical vocabulary, was transmitted into the Middle Ages, albeit in convoluted and disruptive ways.