Mortimer Jerome Adler (December 28, 1902 – June 28, 2001) was an American philosopher, educator, and popular author. As a philosopher he worked within the Aristotelian and Thomistic traditions. He lived for the longest stretches in New York City, Chicago, San Francisco, and San Mateo, California. He worked for Columbia University, the University of Chicago, Encyclopædia Britannica, and Adler's own Institute for Philosophical Research.