 The most important physiologist thinker during Grouchy’s lifetime was her brother in law Pierre-Georges Cabanis. In 1796, two years before the publication of the Letters, but four years after they were first drafted, Cabanis presented a number of lectures on a topic that was central to the most original parts of Grouchy’s response to Smith, namely, the role of the sensations of pleasure and pain in bringing about sympathy, and ultimately morality. His lectures were printed in 1802 under the title Les Rapports du Physique et du Moral. Arguing that morality was the result of reasoning about sensations, Cabanis proposed that “moral properties were nothing but physical properties considered from certain particular points of view” and that 