Oswald von Nell-Breuning SJ (8 March 1890 – 21 August 1991) was a Roman Catholic theologian and sociologist. He is considered to be the originator of modern Catholic social doctrine including its three core principles: personality, subsidiarity, and solidarity. He lectured as an honorary professor at Goethe University at later established his own "Akademie der Arbeit" (Academy of Work). He exerted a strong influence on the social policy program of the Christian Democratic Union of Germany and had a close relationship with the German trade unions.