Kalam cosmological argument

The Kalam cosmological argument is a modern formulation of the cosmological argument for the existence of God. It is named after the Kalam (medieval Islamic scholasticism) from which many of its key ideas originated.^[1] Philosopher and theologian William Lane Craig was principally responsible for revitalizing these ideas for modern academic discourse through his book The Kalām Cosmological Argument (1979), as well as other publications.

The argument's key underpinning idea is the metaphysical impossibility of actual infinities and of a temporally past-infinite universe, traced by Craig to 11th-century Persian Muslim scholastic philosopher Al-Ghazali. This feature distinguishes it from other cosmological arguments, such as that of Thomas Aquinas, which rests on the impossibility of a causally ordered infinite regress, and those of Leibniz and Samuel Clarke, which refer to the principle of sufficient reason.^[2]

Since Craig's original publication, the Kalam cosmological argument has elicited public debate between Craig and Graham Oppy, Adolf Grünbaum, J. L. Mackie and Quentin Smith, and has been used in Christian apologetics.^[3] According to Michael Martin, the cosmological arguments presented by Craig, Bruce Reichenbach, and Richard Swinburne are "among the most sophisticated and well-argued in contemporary theological philosophy".^[4]