Natural theology

Natural theology is an earlier, historically important alternative to natural selection as a means of explaining adaptations.

Natural theologians explained the properties of nature theologically (i.e., by direct action of God). They were highly influential from the 18th century and during Darwin's lifetime.

Important thinkers of this type were John Ray and William Paley.

Darwin himself was much influenced by the examples of adaptation, such as the vertebrate eye, discussed by Paley. Paley explained adaptation in nature by the creative action of God: when God miraculously created the world and its living creatures, He miraculously created their adaptations too.

The key difference between natural theology and Darwinism is that the former explains adaptation by supernatural action, and the latter by natural selection.