In ‘Professor Mackie and the Kalam Cosmological Argument’ (Religious Studies, xx (1984), 367–75), Professor William Lane Craig undertakes to demonstrate that J. L. Mackie's analysis of the kalam cosmological argument in The Miracle of Theism (Oxford University Press, Oxford, 1982) is ‘superficial’, and that Mackie ‘has failed to provide any compelling or even intuitively appealing objection against the argument’ (p. 367). I disagree with Craig's judgement; for it seems to me that the considerations which Mackie advances do serve to refute the kalam cosmological argument. Consequently, the purpose of this paper is to reply to Craig's criticisms on Mackie's behalf.