Complex sentence: After a short teaching stint at Michigan, he taught at Swarthmore College, 1925-44, then spent the remainder of his career until his 1961 retirement at Yale University, where he served as chairman of the Department of Philosophy for many years.
Split into simpler sentences: After a short teaching stint at Michigan, he taught at Swarthmore College from 1925 to 1944. At Yale, he served as chairman of the Department of Philosophy for many years.