Harry J. Gensler, S.J., is retired from Loyola University Chicago. This is his 17th philosophy book; many have been translated into other languages. His main areas are logic, ethics, and religion. Some of his other books include Anthology of Catholic Philosophy (2005); Ethics and the Golden Rule (2013); Ethics and Religion (2016); Introduction to Logic, 3rd ed. (2017); and Ethics: A Contemporary Introduction, 3rd ed. (2018).