Authority on Thomistic philosophy and a neo-Aristotelian thinker. He was a proponent of realist metaphysics and practical ethics.
He obtained his Ph.D. from Harvard University in 1937 and taught at Indiana University from 1937 until 1965, Northwestern University from 1965 until 1973, and Georgetown University from 1973 until 1983.
He was once the president of the Western Division of the American Philosophical Association.
He was born in Evansville, Indiana, and was involved in the Episcopal Church. He also served as the president of the American Catholic Philosophical Association.
He and Alan Watts were contemporaries.