This introduction broaches the question of how naturalism rose to dominance in the modern West. Naturalism in this context is understood as a rejection of belief in the supernatural. This distinctive feature of Western modernity is at odds, not only with its own religious past, but also with what has been true for virtually all other cultures. Whereas it was once impossible not to assume the existence of the supernatural, this has now become one option among others, and one that is typically thought to be lacking in rational support. The book seeks to account for this unique historical development in two related ways. First, it explores the histories of the two key terms in this understanding—‘belief’ and ‘supernatural’—showing how they came to take on their present meanings in the modern period. Second, it shows how advocates of naturalism necessarily subscribe to a progressive view of history that can vindicate the adoption of these two categories in their modern sense.

This chapter gives an account of the origins of our present understanding of the natural/supernatural divide, showing how the terminology of the ‘supernatural’ first emerged in the Middle Ages and gradually assumed its modern form between the seventeenth and nineteenth centuries. The attendant ‘isms’—naturalism and supernaturalism—arrive at the end of this period, during the 1800s. The original context for the naturalism/supernaturalism distinction was neither science nor philosophy, but the sphere of biblical criticism. From there it was imported into a scientific context. The nineteenth century also witnessed attempts to reconstruct the history of science with a view to arguing for a long-standing alliance between naturalism and science. A more accurate portrayal of the relevant history shows, to the contrary, that ‘science’ had been consistently aligned with theistic assumptions about the regularities of nature. These regularities were formalised as laws of nature in the seventeenth century, at which time they were understood as divinely authored imperatives to which nature necessarily conformed. In the nineteenth century, what had originally been understood as expressions of the divine will were simply redescribed in purely naturalistic terms by advocates of naturalism. Ironically, they were now claimed to represent evidence against theistic readings of nature.

David Hume’s famous argument against believing miracle reports exemplifies several key issues relating to the emergence of modern naturalism. Hume uncritically assumes the universal and unproblematic nature of core conceptions such as ‘supernatural’ and ‘laws of nature’. Hume’s argument also presents him with a dilemma. He relies upon the weight of testimony to establish his case against believing miracle reports, but must also contend with the weight of testimony, across different times and cultures, to the existence of the supernatural. Hume resolves this by an appeal to historical progress accompanied by a dubious racial theory. These enable him to discount testimonies emanating from the past and from other cultures. ‘Hume’s dilemma’ has not gone away and, if anything, is even more acute since the traditions and beliefs of non-Western cultures are now more difficult to dismiss on the basis of dubious historical accounts of Western exceptionalism. This dilemma amounts to a tension between the ethics of belief and the demands of epistemic justice.

Can we make sense of the idea that nature imposes certain limits on our activities? Seemingly not if we accept the disenchanted conception of nature that goes hand in hand with scientific naturalism, for it is typical of such a picture that the only source of value is to be found in our desires or utilities, and that it makes no sense to suppose that our activities could be normatively constrained from without – as would be the case if there were an external source of value. My aim in what follows is to explore the possibility of defending this realist picture without inviting the charge that we have succumbed to a speculative metaphysics. To put in the terms presupposed by the typical naturalistic philosopher, the question is whether we can make sense of the idea that nature imposes certain limits on our activities without endorsing supernaturalism. The terms ‘naturalism’ and ‘supernaturalism’ tend to be treated as antonyms, but they have various significations and one of my tasks will be to disambiguate them, to agree with the naturalist that supernaturalism can be suspect, but deny that it follows from this that there is no external source of value, nor that we must be atheists, nor even that the term ‘supernaturalism’ should be dispensed with.