He fought bravely and consistently for freedom of thought and speech on religious matters and mediated between the academic and the public sphere. In this regard, he shared much in common with his disciple Gabriel Wagner, who subsequently objected to Thomasius' religious metaphysical beliefs.[1] In law, he tried to prove that the rules of Roman law, which contradicted his own principles of natural law, had never actually been accepted and were therefore invalid; he also tried to legitimize his own principles by showing them to be common law built on Germanic foundations. In this way he contributed to the creation of scholarship of private law separate from that of Roman law.