In 1785, Jacobi became the focus of attention in the philsophical dispute due to his work on the ›Lehre des Spinoza‹ (Spinoza’s Theory) and his quarrel with Mendelssohn concerning Lessing’s real or alleged Spinozism. It did not begin with the publication of Jacobi’s letters and of Mendelssohn’s ›Morgenstunden‹ (Morning Hours) in the fall but rather had already been looming in the previous letters and escalated during the course of the year, fed by rumors and fears. Among the people with whom he corresponded, Hamann must once again be singled out, Jacobi’s »good-hearted father, friend and brother«, and next to him Princess Gallitzin, Goethe and Herder.