Michael Darwin Morley is an American mathematician, currently professor emeritus at Cornell University. His research is in advanced mathematical logic and model theory, and he is best known for Morley's categoricity theorem, which he proved in his Ph.D. thesis "Categoricity in Power" in 1962. His formal Ph.D. advisor was Saunders MacLane at Chicago University, but he actually finished his thesis under the guidance of Robert Vaught in Berkeley.
