What is a Number? Augustine’s Philosophy of Mathematics

James Bradley


In De Libero Arbitrio, Augustine of Hippo presents an argument for the existence of God. Because the argument depends in an essential way on mathematics, Augustine expa nds at some length on its nature. This talk will examine the implications of his views for the four classical questions of the philosophy of mathematics: In what sense are mathematical assertions true? What is the nature of mathematical objects, for exam ple, numbers? Since such objects seem immaterial but we are material beings, how do we acquire knowledge of them? How do we account for the astonishing effectiveness of mathematics in describing the physical world? Also, Augustine’s views on math ematics have implications for many other questions. If there is time, this talk will address two in particular: How are we to understand God’s freedom? And how are we to understand the nature of logic?