Aquinas's Critique of the Argument from the Actual Infinite

This post, from Siris, argues that St. Thomas Aquinas provided the basis for rejecting versions of the Kalam Cosmological Argument that appeal to an actual infinite, beating Wes Morriston to the punch by eight and a half centuries.

Wikipedia entry on actual infinities

This is a wikipedia entry on actual infinities. William Lane Craig defends his argument for the beginning of the universe by maintaining that an actual infinity is impossible.