Natural Theology stood for much of the nineteenth century as one of the most widely read and taught statements of natural theology in the English speaking world, required reading at Cambridge University for decades and a significant influence on how educated readers, including for a period the young Charles Darwin, framed the relationship between the study of nature and belief in a designing God. Its central watchmaker analogy became so well known that later discussions of the design argument, whether sympathetic or critical, routinely engage with Paley's specific formulation rather than the argument in more abstract or general form.
The book's standing changed decisively following the publication of Darwin's theory of evolution by natural selection, which offered a naturalistic mechanism, unguided variation filtered by differential survival, capable of producing the appearance of purposeful design that Paley had argued could only be explained by an intentional designer. Since then Natural Theology has remained a central reference point in the philosophy of religion less as an accepted proof than as the classical statement of an argument that subsequent debate over evolution, design and the nature of scientific explanation continues to engage with directly, for and against.