The intensity (and the lack of ceremony) that Diderot brought to their conversations in the Little Hermitage is now a thing of legend. During sometimes heated exchanges, the philosophe cajoled, contradicted, and even reached out and pounded on Catherine’s leg as he would while speaking to d’Holbach or Grimm. In a letter that the empress sent to Voltaire in January 1774, she admitted to being impressed by the limitless imagination of the most “extraordinary man” she had ever
