Anthony Perry Morse (1911–1984) was an American mathematician who worked in both analysis, especially measure theory, and in the foundations of mathematics. He is best known as the co-creator, together with John L. Kelley, of Morse–Kelley set theory. This theory first appeared in print in Kelley's General Topology. Morse's own version appeared later in A Theory of Sets.He is also known for his work on the Morse–Sard theorem and the Federer–Morse theorem.