The Existence of God is a 1979 book by British philosopher of religion Richard Swinburne, claiming the existence of the Abrahamic God on rational grounds. The argument rests on an updated version of natural theology with biological evolution using scientific inference, mathematical probability theory, such as Bayes' theorem, and of inductive logic. In 2004, a second edition was released under the same title.
Swinburne discusses the intrinsic probability of theism, with an everlastingly omnipotent, omniscient and perfectly free God. He states various reasons for the existence of God, such as cosmological and teleological arguments, arguments from the consciousness of the higher vertebrates including humans, morality, providence, history, miracles and religious experience. Swinburne claims that the occurrence of evil does not diminish the probability of God, and that the hiddenness of God can be explained by his allowing free choice to humans. He concludes that on balance it is more probable than not that God exists, with a probability larger than 0.5, on a scale of 0.0 (impossible) to 1.0 (absolutely sure).