 In 1784, Hofmann was made Chair of Philosophy in Mainz as part of the progressive reforms of Elector Friedrich Karl von Erthal that had made the University of Mainz one of the centres of Catholic Enlightenment.Like many other future members of the , he was a member of the secret society of the "Illuminati" (under the name "Aulus Persius") but the Illuminati were outlawed in 1785 and the lodge dissolved soon after.Hofmann first taught History of Philosophy until 1791, when he also became chair of natural law.