One of my favourite books as an undergraduate was The Meaning of Jesus: Two Visions, co-authored by N. T. Wright and Marcus Borg. In that volume, two top scholars with almost diametrically opposed views came together to justify their positions and to respond to each other’s, helpfully charting a spectrum of scholarly opinion on historical Jesus questions. En route, the discussion was also sprinkled with intellectual virtues: the courage to engage constructively in a joint project, a charitable hermeneutic of opponents, and a good dose of humility and civility – none of which obscured genuine disagreement. At its best, this volume on natural theology has many of the same strengths, and rather than merely introducing a topic or presenting an argument, it curates a conversation and a debate. There are more encyclopaedic and detailed scholarly collections on natural theology, notably The Oxford Handbook of Natural Theology.Footnote ¹ However, the present volume is distinctive in inviting contributors to actively advocate for (rather than merely describe) their chosen position, and then face the scrutiny of ‘responses’ from all of the other contributors, before being afforded a ‘reply’.

The five views are as follows. (1) Taliaferro’s ‘contemporary view’ attempts to repristinate classical arguments for the existence of God, including a cosmological argument, a teleological argument, and (briefly) an argument from consciousness. (2) Pinsent’s ‘catholic view’ defends the Vatican I view that God can be known by the natural light of human reason and leans on Aquinas’ category of supernaturalis as something that transforms nature. Given that humans can be infused with supernatural grace, he argues that the categories of natural and supernatural can cut across both the knowing subject and the known object (leading to four permutations in the form of natural/supernatural knowledge of the natural/supernatural). (3) McGrath’s ‘classical view’ begins with an historical genealogy that uncovers four kinds of natural theology: (a) the exercise of natural human reason, (b) a form of reasoning independent of revelation, (c) a theology of nature, and (d) a natural tendency of the human mind towards God. He subsequently proposes a ‘big-tent’ version of natural theology that embraces all of these variants and also goes beyond exclusively rational argument to include imagination and emotion. (4) Moser’s ‘deflationary view’ contends that the available arguments for the existence of ‘God’ fail primarily because they are not arguments for a distinctively Christian God who is worthy of worship. As an alternative, he proposes an argument from religious experience as more consistent with biblical material, even though it does not rely on publicly available evidence. (5) McDowell’s ‘Barthian view’ introduces Barth’s theological method centred on revelation and shows how it entails that natural theology is a ‘theo-grammatical mistake’. His account concentrates on Barth’s Gifford lectures and the Church Dogmatics, rather than the earlier acerbic Barth of Nein!

The trajectory thus goes from optimistic to pessimistic views of natural theology. However, grouping contributions into pro- (the first three) and anti- (the last two) natural theology camps only yields a simplistic categorisation. The most interesting moments, to my mind, arise during disagreement within camps or surprising alliances or concessions between them. As an example of the former, Moser and McDowell reach a similarly negative evaluation of natural theology by very different, contested means: Moser decries what he sees as Barth’s axiomatic account of revelation and an accompanying dismissal of human reasoning, while McDowell is sceptical of Moser’s pivot to evidential arguments from religious experience, on the grounds that religious experience is culturally conditioned and ultimately fails as an apophatically appropriate vehicle for capturing a transcendent God. As an example of a noteworthy concession, McDowell acknowledges that Barth’s rejection of the analogia entis targets neo-Thomist usage but fails to do justice to Thomas’ own thought.

Any presentation of a handful of views is likely to raise questions about the criteria of selection and missing perspectives. The editors restrict themselves to an internecine Christian debate (whereas the Oxford Handbook branches out into other major religious traditions), and this seems a sensible decision to make the conversation more manageable. Within those confines, the five views selected represent a range of influential positions, but if one were to identify lacunae, I would prioritise the two additional views. First, a feminist view would be particularly valuable in interrogating the ‘natural’ of natural theology, given (for example) the gendering of nature-culture binaries and debates around biological essentialism versus social constructivism.Footnote ² Accounts of nature are never politically neutral, and observations on how appeals to a ‘natural order’ have been wielded oppressively might give further pause to any hasty embrace of natural theology. Second, a panentheist view (say from Eastern Orthodoxy or process theology) would provide a metaphysical warrant for pursuing natural theology, shifting the conversation from largely epistemological terrain. Such additions would interestingly expand the conversation and perhaps spice it up with some more colourful disagreements.

Perhaps the most striking features of the juxtaposition of the five views is that they do not simply deploy different arguments or reach different conclusions, but rather the disagreement runs far deeper into questions of definition and methodology. Taliaferro and Moser take a narrow view, largely restricting natural theology to arguments for the existence of God that are intelligible to shared human reason (and thus independent of revelation). Consequently, they primarily use ahistorical philosophical tools and literatures (largely analytic ones, in Moser’s case) to defend or critique these arguments. The other three contributors allow for far broader definitions and their methodologies reflect this capaciousness. Pinsent’s method is largely confessional, rooted in the constraints of the Roman Catholic tradition, but also attempting to make broader arguments for the viability of a neo-scholastic account. For McGrath, a descriptive historical genealogy of the term shades into a normative case for multiple varieties of natural theology operating together. McDowell, by contrast, adopts a theological-hermeneutical approach in keeping with the Barthian dictum that theology must determine its own methodology. A similar diversity is evident in the style of the responses. Moser, for instance, rigorously represents his own position in replies by consistently taking others to task for question-begging and for proposing arguments for a God who is not worthy of worship. Others are less concerned with championing their own view in responses and focus on raising questions that arise in the other views. At times one could be forgiven for mistaking McDowell’s interventions as representing Nicholas of Cusa or indeed Nicholas Lash rather than Karl Barth; but, in my estimation, this makes them all the more exciting than simply rehearsing a Barthian critique as it might apply to other positions.

The diversity of approaches and definitions (and not merely positions) manifests as both a strength and a weakness. On the plus side, it catalogues the different versions of natural theology on offer and the richness of the topic. Furthermore, it demonstrates how the choice of method can influence one’s conclusions. However, the diversity also threatens the overall coherence of the conversation. Since contributors adopt quite different working definitions some discussions terminate in uninteresting semantic disagreements or interlocutors talking past one another. And because views diverge simultaneously on multiple different ‘levels’ (definitional, methodological, stylistic, argumentative content) it can be difficult to trace the root of disagreements (which often lie in deeper fundamentals such as whether human reason is tradition-dependent or something closer to the Enlightenment vision of a timeless, publicly available method). These misgiving notwithstanding, this book largely succeeds in demonstrating that genuine conversation is often more pedagogically fruitful than standalone monologues. Furthermore, it makes a significant contribution to introducing newcomers to a crucial debate in Christian theological methodology.