 From 1938 to 1940, he was ordinary university professor at Pontifical Urbaniana University, where he was first Extraordinary (1939) and then Ordinary Professor (1941) of Metaphysics.He later taught Philosophy of Religion (1948-1956; 1970-1973).In 1960, he founded the first ever "Institute of the History of Atheism", which was later renamed "Research Institute on Non-Belief and Culture".