The term ‘natural theology’ provokes a variety of reactions, spanning from whole-hearted endorsement to passionate rejection. It is polarising. To some, the label ‘natural theology’ implies a departure from the triune God revealed in and as Jesus of Nazareth, suggesting an unwarranted form of epistemological hubris that undermines the essence of Christian faith. Conversely, in other circles, a rejection of natural theology is perceived as a fideistic posture, indicative of an uncritical and possibly naïve approach to religious epistemology.
Charged as it is with polemical and pejorative undertones, this debate begs for an intervention. If the scholarly community is to engage constructively with the concept and practice of natural theology – either by way of acceptance, rejection or something in between – clarity in its definition and identification is imperative. For, as Alister McGrath aptly notes:
Any discussion about whether natural theology is helpful or destructive, proper or improper, wise or foolish, authentically Christian or inherently pagan, is critically dependent on how the notion is defined, and the ideational framework within which it is located.Footnote 1
One problem, though, is the fact that there appear to be substantial divergences amongst various scholarly sub-communities over what exactly counts as natural theology. From analytic philosophers of religion to the followers of Karl Barth, there exists a wide array of definitions of the enterprise. The aim of this paper, then, is to try to shed some light on three of the most common definitions in contemporary scholarship, to provide clarity about the ways in which they differ, and to propose some conceptual refinements in the hope that, if adopted, more fruitful discourse may take place in relation to this much-debated and interdisciplinary phrase. That being said, we do not intend to ‘police language’ and argue that there is only one proper way to understand ‘natural theology’. ‘Concepts have histories’,Footnote 2 and this is especially the case with the term theologia naturalis, ‘which could arguably be translated as either “a natural theology” or “a theology of nature”’.Footnote 3 Rather than trying to settle the dispute as to what actually constitutes ‘natural theology’, we shall instead draw upon insights from the philosopher David Chalmers, so that our focus will shift away from semantics towards substance, and away from reifying essentialist views of language towards the roles various projects seek to fulfil and the properties that a piece of reasoning must have if it is to fulfil such roles.Footnote 4
In this register, we begin by identifying three projects which have been labelled as ‘natural theology’. We then sketch Chalmers’ proposal about how we might diagnose whether a disagreement involving a key term is merely a matter of how certain words are used or is a substantive disagreement. In keeping with Chalmers’ advice, rather than try to settle the (arguably irresolvable) semantic question of what the label ‘natural theology’ means, we propose trying instead to identify the different roles that each of three projects commonly bearing that label appear to be striving to fulfil.
Divergent projects
The following is a representative sampling of definitions of natural theology offered by various contemporary analytic philosophers of religion:
The renaissance of Christian philosophy over the last half century has served to reinvigorate natural theology, that branch of theology that seeks to provide warrant for belief in God's existence apart from the resources of authoritative, propositional revelation.Footnote 5
Natural theology is a program of inquiry into the existence and attributes of God without referring or appealing to any divine revelation.Footnote 6
Natural theology is the practice of philosophically reflecting on the existence and nature of God independent of real or apparent divine revelation or scripture.Footnote 7
Natural theology…originally referred to (and still sometimes refers to) the project of arguing for the existence of God on the basis of observed natural facts… It does, however, avoid appeals to special non-natural faculties (ESP, telepathy, mystical experience) or supernatural sources of information (sacred texts, revealed theology, creedal authorities, direct supernatural communication).Footnote 8
I understand by bare natural theology the attempt to demonstrate the existence of God by arguments (deductive or inductive) beginning from premises describing very general and evident public phenomena.Footnote 9
Natural theology is the endeavour to support the truth or rationality of theism using only the resources of natural human reason. Natural theology, as opposed to revealed theology, may not appeal to any premise that presupposes the authenticity of a particular alleged revelation or the supposed authority of any scripture. Only premises certifiable by the application of the usual tools, standards, and methods of intellectual inquiry are permissible.Footnote 10
Although there exist minor variations, it seems to us that these authors are mostly unified around an understanding of what natural theology seeks to accomplish, what it seeks to avoid and what it seeks to rely upon. Consider the following synthesis, which we will designate NT1 (or ‘Natural Theology According to Analytic Philosophy’):
NT1 (Natural Theology According to Analytic Philosophy)
The project which involves bracketing off any appeals to special revelation, supernatural sources of information, and premises that presuppose the authenticity of specific religious claims or scriptures, while relying instead only on things such as natural human reason, observed facts of the natural world, philosophical reflection, and premises widely accepted by rational individuals, in an effort to argue for the existence (and perhaps also certain attributes) of a divine being.
By contrast, several contemporary theologians, including Alister McGrath and Christopher Brewer, are hesitant to offer a single definition of natural theology, opting instead to create extensive taxonomies identifying different types of natural theology.Footnote 11 N. T. Wright, for his part, cites some of these taxonomies – seemingly acknowledging that they have some (albeit limited) usefulness – before gesturing towards a more basic framework wherein there is:
W1. The apologetic task of ‘natural theology’ – trying to convince the sceptic without appealing to ‘inspiration’.
W2. The explanatory task, drawing out ways to hold together the truth of God and the truth of the world.Footnote 12
Wright appears to acknowledge that ‘natural theology’ can be understood in the way that it is characterised by analytic philosophers. But that is not the only way that it can be understood. What we have labelled as W2 points to a way in which some forms of enquiry which do in fact appeal to theological sources of information or the authenticity of specifically Christian claims can be labelled as ‘natural theology’. By way of synthesis, such forms of enquiry, which we will designate NT2 (or ‘One Type of Natural Theology According to Contemporary Theologians’) might be characterised thus:
NT2 (One Type of Natural Theology According to Contemporary Theologians)
The project which involves drawing upon some premises that are either rooted in or presuppose the authenticity of specific theological claims or theological sources of information, in an effort to acquire a Christian understanding of (or posture toward) the natural world.
And then, finally, there is Karl Barth and those who follow in his footsteps. At the heart of Barth's much-misunderstood theological epistemology is the dual commitment that Jesus is the objective reality and possibility of divine revelation, and that the Holy Spirit is the subjective reality and possibility of divine revelation.Footnote 13 Put another way, Barth argues that the ‘objective’ possibility of human knowers arriving at knowledge of God is dependent upon God entering into the realm of human knowability in the incarnation, and the ‘subjective’ possibility of discerning such revelation takes place in the transformative power of the Spirit by which the objective reality of revelation there and then becomes present to us – through the proclamation of the church as based upon the biblical witness to Jesus – here and now.Footnote 14 For Barth, there is no other legitimate means by which God can be known. This is the larger context in which one can (partially) make sense of his earlier definition of natural theology:
[E]very (positive or negative) formulation of a system which claims to be theological, i.e. to interpret divine revelation, whose subject, however, differs fundamentally from the revelation in Jesus Christ and whose method therefore differs equally from the exposition of Holy Scripture.Footnote 15
What this definition implies (when taken in conjunction with the argument of the Church Dogmatics), is that the ‘objective’ possibility of natural theology depends, for Barth, on the assumption that there is some source other than Jesus which has the capacity to reveal God. Similarly, the ‘subjective’ possibility of natural theology depends on the assumption that human beings have the capacity, apart from the work of the Holy Spirit, to arrive at such knowledge.
Cast in this light, natural theology might be understood in exceptionally broad terms, which we will designate as NT3 (or ‘Natural Theology According to Karl Barth’):
NT3 (Natural Theology According to Karl Barth)
The project which involves arriving at theological claims about God, the world, and/or the relationship between the two, which does so either by (i) appealing to some source other than God's self-disclosure in Jesus as witnessed to in scripture, or (ii) attempting to acquire such theological knowledge via a latent natural human capacity rather than by the work of the Holy Spirit.
For Barth, the task of theology is to reflect ever anew upon the event of revelation in which God is made known in the concrete history of Jesus by the illuminating work of the Holy Spirit. Natural theology is any project which deviates from such a task. In this way, it is sinfulness itself – the fact that our minds are enslaved to the consequences of sin – that makes us believe that natural theology is both possible and desirable.
It appears, then, that there is considerable divergence concerning the definition of ‘natural theology’ between various scholarly sub-communities who frequently use the term. And yet the three projects we have highlighted between them account for the vast majority of the intellectual activities that have borne the label ‘natural theology’. But what is at stake here amidst such diverging definitions of natural theology? David Chalmers has made the case that many philosophical disputes about questions of the form What is x? are apt to be diagnosed as merely ‘verbal disputes’ – that is, as disagreements merely about how certain words should be used, but nothing more. By way of illustration, consider, for example, debates in epistemology about the nature of epistemic justification. Internalists hold that justification is a property that one's beliefs can have only when they are based on evidence that is (in some suitable sense) within one's purview. Externalists hold that justification is a property that one's beliefs can have in virtue of being produced by a causal process that stands in a certain objective relation to the world, irrespective of whether one is aware of that relation. Chalmers suggests that we might test whether a disagreement such as this one is substantive or merely verbal by employing what he calls ‘the subscript gambit’.Footnote 16 The way we proceed is to bar the use of the term ‘justification’ and give the label ‘J1’ to justification as internalists understand it and ‘J2’ to justification as externalists understand it. This clears the way for us to consider whether there is any substantive disagreement between the two sides. Do they, for example, disagree about whether J1 is more valuable than J2? Do they disagree about whether someone's being in a position to use her belief as a premise in practical reasoning requires that her belief possesses J1, or only J2, or both J1 and J2? And so on. Chalmers suggests that one important lesson we can draw from all of this is that rather than expending large amounts of energy on arguing about whether this or that account provides the best definition of a certain word or phrase, we would do much better to focus on thinking about what roles a given property (or set of properties) is able to play in our theorising about the world.Footnote 17 This strikes us as wise counsel, particularly when it comes to disputes about natural theology. After all, unlike an item of everyday discourse such as the word ‘belief’, ‘natural theology’ seems to be a quasi-technical term. The project of trying to answer questions of the form What is x? would be especially unpromising in the case of natural theology, given that there arguably isn't any ordinary-language usage to guide us (as evidenced by the widely varying definitions outlined above).
Divergent aims
We have identified three different ‘projects’ connected with the term ‘natural theology’: one associated with analytic philosophy of religion; one identified by various theologians such as Wright, McGrath, and Brewer and one associated with what Barth rejects. Be that as it may, we have no desire to ‘police language’ and to assert that the term ‘natural theology’ properly designates only one of these endeavours. In line with Chalmers’ advice, however, what we can fruitfully do is to consider the roles that the various activities termed ‘natural theology’ have been supposed to play in our thinking about the world and the divine, and to consider in turn what properties something would have to have in order to be capable of fulfilling such roles.
Before going further, we need to be clear about what type of thing could even be a candidate for playing the roles that various kinds of natural theology are supposed to play. Often books are deemed ‘works of natural theology’ and authors are called ‘natural theologians’. But first and foremost, it is arguments, or if one prefers, pieces of reasoning, that are or are not instances of natural theology. The sense in which authors are natural theologians and books are works of natural theology (however conceived) is derivative of this primary sense, in which it is arguments or pieces of reasoning that bear certain properties that we are about to discuss.
Regardless of what term we use to describe the three projects identified, we propose that each aspires to fulfil different roles. Consider the above definitions of natural theology from various analytic philosophers of religion, summarised as NT1. It seems to us that, on the basis of what they bracket off, they are all attempting to pick out an intellectual activity which strives to operate on an intellectual playing field that is theologically neutral, so to speak. The overarching concern, in other words, is to avoid stacking the deck or begging the question in favour of some theological truth-claim or worldview. As such, we propose that something like the following three properties (at a bare minimum) must be present in order for a piece of reasoning to strive to operate on a level intellectual playing field in the quest for the truth about the divine:
A. The argument can in principle serve as a means by which a non-adherent can investigate a theological truth-claim without already having to accept the authenticity of any theological claims that are distinctive of a religious worldview.
B. The argument can in principle serve as a means by which the adherents of a given worldview can try to ascertain how much justification a theological claim might have, if they were to bracket off premises that presuppose the authenticity of particular theological claims that are distinctive of that worldview.
C. The argument can in principle serve as a means by which adherents of a given worldview can try to persuade non-adherents of the truth of a particular theological claim whilst attempting not to beg the question in favour of the truth-claim.
To illustrate this, consider a straightforward deductive version of the moral argument for theism that goes like so:
(P1) There are objective ethical truths.
(P2) There cannot be objective ethical truths without God.
(C) Therefore, God exists.Footnote 18
At the broadest level, we can distinguish between two kinds of ‘data’ in this argument: on the one hand, there is a claim about some state of affairs in the world (call this the primary data), and on the other, there is a claim about some conceptual or metaphysical or probabilistic connection between that state of affairs and the target theological claim (call this connecting principle the secondary data). Crucially, however, whether or not one contests the plausibility of either the primary or the secondary data, the argument itself does not require an enquirer to presuppose the authenticity of the theological claim ‘God exists’ to assess the argument's merits. Thus, the argument bears property A outlined above.
Furthermore, regardless of whether the argument itself proves convincing, it likewise bears property B, in that a person of faith might try to consider its reasoning to ascertain how much justification their belief in the existence of a particular deity might have if they were to bracket off distinctively theological beliefs from their evidence base. And finally, whether or not one ought to do so, and whether or not it proves efficacious, the argument can likewise be wielded by adherents of a theistic worldview to try to persuade those unconvinced of theism that theism is true, on the basis of premises which attempt not to beg the question in favour of theism; hence it bears property C. Consequently, this version of the moral argument can be said to fulfil the role of striving to operate on a level and theologically neutral intellectual playing field, even if the premises are contested or the argument proves to be unconvincing.
Similar things can be said in relation to typical construals of the Kālām cosmological argument,Footnote 19 the modal ontological argument,Footnote 20 and the argument from the fine-tuning of various physical constants in the universe.Footnote 21 Be that as it may, as we shall demonstrate below, it seems to us that some forms of reasoning can bear these various properties and fulfil the aforementioned role – evincing a family resemblance to the basic gist of NT1 – and yet are artificially excluded by the characterisation of natural theology by analytic philosophers quoted earlier. Put another way, there are some types of data and some potential theological areas of adjudication which we believe can be brought into the fold for a revised understanding of NT1.
A different role seems to be in view for NT2. Here, rather than being focused primarily upon what one brackets off, the project seems far more interested in the goal of a particular form of reasoning.Footnote 22 This role, far from striving after theological neutrality, is instead directed towards drawing upon the resources of a theological tradition in order to confirm, contribute to, enhance, challenge, displace and/or transform one's understanding of the natural world. Understood thus, something like the following property would (at a minimum) need to be borne by a particular argument to fulfil this role:
D. The argument can in principle serve as a means by which someone committed to a certain theological truth-claim (or set of truth-claims) can inquire as to what implications that (or those) truth-claim(s) might have for thinking about some aspect(s) of the natural world.
On this point, consider one brief example. According to Wright, there is a universal recognition across time and cultures that certain aspects of the human condition are important. He names seven: justice, beauty, freedom, truth, power, spirituality and relationships. Without going through all the contours of his argument, one of the central threads is Wright's contention that the Christian belief in the new creation – paradigmatically and prototypically made known in Jesus’ resurrection from the dead – is the basis upon which one can make sense of why such things are deemed to be significant by nearly all human beings. At the heart of this Christian hope is a future in which injustice does not exist, beauty is properly celebrated, freedom is unrestricted, truth eclipses all lies, power is wielded responsibly, spirituality is fully realised and healthy relationships form the basis for the worldly community. In other words, he draws upon a theological truth-claim (i.e. this vision of the new creation) in order to think about and make sense of some aspect of the natural world (i.e. the universal impulse to value those seven features of the human condition).Footnote 23
This component of his argument therefore bears property D and fulfils the role of drawing upon theological truth-claims in order to reassess and/or rethink one's understanding of nature. Of course, one might dispute Wright's claim that the seven identified features are universally recognised as being important, just as one might also dispute Wright's characterisation of the ultimate Christian hope (or, perhaps, even if one agreed with both, one might dispute his conclusion that the new creation best makes sense of why such things are deemed to be significant). But the point remains that his argument bears the requisite property, and fulfils the identified role, of NT2.Footnote 24
This brings us, finally, to the exceptionally broad role (which Barth hopes does not get fulfilled, but laments that it often does) one might strive to fulfil in order to fall under NT3. As we understand it, the central role of NT3 is to conduct theological enquiry that operates independently of the revelation of the Christian God in Jesus and/or the Holy Spirit's illuminating work. Consequently, for a piece of reasoning to fulfil this role, at least one of the two properties, at a minimum, must be borne:
E. The argument can in principle serve as a means by which one may arrive at theological truth-claims on the basis of some source other than the Christian God's self-disclosure in Jesus.
F. The argument can in principle serve as a means by which one may arrive at theological truth-claims on the basis of a latent natural human capacity rather than by the work of the Holy Spirit.
From this perspective it is possible to explain the notable phenomenon wherein the Deutsche Christen of the 1930s have become associated with ‘natural theology’ in Barthian circles.Footnote 25 As Barth understood them, the Deutsche Christen made an abhorrent theological claim on the basis of problematic theological reasoning: that the historical rise of Hitler and the Nazi regime, as well as the perceived cultural and racial supremacy of the Aryan people, were not only indicative of but directly aligned with God's will. For their primary data, it appears as though they relied upon mere observation of the unfolding socio-political events in Germany and their idealisation of aspects of German national identity, history and the perceived racial superiority of the Aryan people. The connecting principle they presumably employed (the secondary data) was a theological commitment to providence, a Lutheran two-kingdoms theology and/or a belief about the divine will manifest through the state. On the basis of premises such as these, they arrived at their target proposition.
Understood thus, this piece of reasoning bears property E, given that its primary appeal to the unfolding events in Germany is a source other than the Christian God's self-disclosure in Jesus. What's more, depending upon how it is formulated, it may very well also bear property F, in that the person making the argument might assume that they arrived at such a conclusion on the basis of natural human capacities rather than the work of the Holy Spirit. Either way, it fulfils the role of NT3 as Barth understands it.
What we glean from this is that NT3 is incredibly broad. By definition, it encompasses all instances of NT1. However, so far as we can see, it also encompasses at least some instances of NT2. Both Wright's appeal to seven universal features of the human condition and the Deutsche Christen sentiment, for example, fall under both NT2 and NT3. This indicates that the relationship between these three projects is rather complex, and merits further consideration. In the quest for clarity, we propose that there is a need to offer some conceptual refinements to two of the above projects that, we believe, will foster a more conducive environment for scholarly discourse.
Refining the definitions
Refining NT1
We have seen that analytic philosophers of religion are highly unified around a particular understanding of what natural theology involves, which we have tried to capture as follows:
NT1 (Natural Theology According to Analytic Philosophy)
The project which involves bracketing off any appeals to special revelation, supernatural sources of information, and premises that presuppose the authenticity of specific religious claims or scriptures, while relying instead only on things such as natural human reason, observed facts of the natural world, philosophical reflection, and premises widely accepted by rational individuals, in an effort to argue for the existence (and perhaps also certain attributes) of a divine being.
The role that this project is seeking to fulfil can be summarised as that of providing a theologically neutral means for attempting to adjudicate the truth-claims of a theological worldview without already having to presuppose any of the worldview's distinctive claims or any special cognitive abilities that are likely to exist only if the worldview is true. It is because NT1 is striving to fulfil this role that it must involve the aforementioned restrictions on the kinds of data that arguments can draw upon if they are to count as contributions to NT1. There are two respects, however, in which we wish to challenge some of the restrictions outlined by the analytic philosophers of religion quoted earlier as arbitrary, unnecessary, and even obstructive, given the aforementioned role that NT1 is plausibly striving to fulfil.
The first thing we wish to challenge is the restriction of the proper subject matter of NT1 that is reflected in the quotes earlier. All of the quoted analytic philosophers of religion restrict the subject matter of natural theology just to God's existence and nature (where the latter is taken to refer to God's essential attributes). But if the goal of NT1 is to try to discover whether a given theological worldview – say, Christianity – is true without presupposing any distinctive tenets of Christianity or any cognitive abilities that are likely to be real only if Christianity is true, why would we wish to limit ourselves to investigating only the existence of a deity with the generic theistic attributes? Not only would that limitation be unnecessary given our goal, it would arbitrarily prevent the NT1-natural theologian from going any further than establishing the existence of a being with the attributes that most adherents of the Abrahamic traditions would be likely to agree upon. As far as we can see, there is nothing to prevent a much wider range of theological topics than this being adjudicated by means of the sort of agnostic-friendly methodology that is vital for the role that NT1 strives to fulfil. In addition to adjudicating the existence and essential attributes of God or gods, that expanded range of topics includes things such as:
• contingent intrinsic attributes of God or gods (e.g. contingent desires)
• the actions of God or gods in history
• the logical coherence of tradition-specific doctrines (e.g. the Incarnation, Tawhid)
• the truth of tradition-specific doctrines
• the scope and limits of human knowledge concerning theological matters
• meta-epistemological claims about the sorts of epistemic properties that a person's religious beliefs could possess if their worldview were true.
Our second quibble with the framing of NT1 concerns the idea (reflected in some of the earlier quotes from analytic philosophers of religion) that it is impermissible to appeal to scripture or religious tradition. Perhaps the authors in question would clarify their positions if pressed, but in any case, our concern is that merely referring to the content of a religious scripture or tradition in one's argument by way of noting what that religion asserts doesn't prevent one's argument being a means of adjudicating the truth of the claims of a particular religious worldview without presupposing the authenticity of any claims that are distinctive of that worldview or presupposing any cognitive abilities that are likely to be real only if that worldview is true. It is only when one's argument treats the contents of scripture or tradition as being true (or probably true) just in virtue of their being allegedly divinely revealed that one's argument fails to be a contribution to that project. The same point applies, mutatis mutandis, to the contents of creeds, assertions by ecclesial authorities, private visions and so on.
In support of our challenges to what we see as arbitrary and needless restrictions on NT1 given the roles that NT1 aims to fulfil, we offer two case studies that we suggest clearly constitute legitimate attempts to fulfil the roles to which NT1 aspires, and yet involve both appeals to scripture and the attempt to adjudicate topics other than the bare existence and essential attributes of God.
The first is the project of trying to establish the historicity of events that are described in religious texts, the most prominent example of which is the effort to argue for the historicity of Jesus’ purported resurrection.Footnote 26 This project typically involves applying standard historical methods to argue for the reliability of certain key portions of the historical narrative in the Pauline epistles (e.g. 1 Cor 15:3–8) and the New Testament Gospels (e.g. Mark 16:1–8; Luke 24:36–48) and then goes on to argue that a bodily resurrection is the best explanation for the experiences reported in those texts. Crucially, the New Testament texts at issue are not being treated as probably true in virtue of being divinely revealed. Rather than being assumed, the historicity of the relevant portions of the narrative is being argued for on the grounds that those portions allegedly exemplify properties that a secular historian will recognise as evidence of authenticity. So although this approach in some sense ‘appeals to’ religious texts, it does so in a way that is fully consistent with the roles that NT1 aspires to fulfil. We take this to be what Wright is getting at when he contends in his Gifford Lectures that Jesus and the Bible are just as much part of ‘nature’ as are any of the data that figure in cosmological or teleological arguments, and as such should not be arbitrarily excluded from the possible sources of natural theology.Footnote 27
As a second case study, consider arguments for the logical coherence of the doctrine of the Trinity.Footnote 28 The way such arguments standardly work is that they begin with a set of propositions which they take to characterise the doctrine of the Trinity, namely: that there are three divine persons and yet just one divine substance. Call this the three-in-one claim. The author then proceeds to put forward a model (a description of a way that things could be), which, if coherent, entails that the three-in-one claim is coherent. For example, Brian Leftow offers a model involving a dancer time-travelling back to a point earlier in the evening and joining her earlier self on stage, and then time-travelling again and joining the two earlier versions of herself on stage.Footnote 29 The claim is twofold: (i) that this scenario is genuinely coherent, and (ii) that if it is coherent, then the three-in-one claim is also coherent. Whether or not one is persuaded of the model, and whether or not one is convinced that trinitarian doctrine is coherent, it should be clear that this sort of project is totally compatible with the role that NT1 aspires to fulfil: it in no way depends upon treating the contents of the Christian scriptures and creeds as being true in virtue of their being allegedly divinely revealed. Rather, it merely involves drawing inferences about what would be the case were Christianity true, and to that end, it involves exercising only our ordinary perceptual and inferential abilities to read and interpret the relevant texts and make inferences about what reality would be like were the content of those texts true. Hence, arriving at the characterisation of the doctrine of the Trinity (the three-in-one claim) doesn't involve relying on divine revelation understood as divine revelation. As for the construction of a model and the assessment of whether it is coherent, that task involves only our ordinary abilities for conceiving scenarios and detecting incoherence.
The following, then, is our proposed refinement of NT1, which we will designate as NT1* (or ‘Natural Theology as an Agnostic-friendly Means of Worldview Adjudication’):
NT1* (Natural Theology as an Agnostic-friendly Means of Worldview Adjudication)
The project which involves bracketing off any appeals to sources of information that are likely to be reliable only given the truth of certain theological worldviews and any premises which presuppose the authenticity of specific religious claims or scriptures (i.e., insofar as religious texts are used in a piece of reasoning, their use cannot be on the basis that they are allegedly authoritative or divinely revealed) while relying instead only on things such as cognitive abilities whose existence is widely accepted, observed facts of the natural world, philosophical reflection, and premises widely accepted by rational individuals, in an effort to argue for any claim about or in relation to God or gods.
Refining NT2
Earlier we synthesised the characterisations of a distinct project by theologians such as Wright, McGrath and Brewer, and offered the following summary:
NT2 (One Type of Natural Theology According to Contemporary Theologians)
The project which involves drawing upon some premises that are either rooted in, or presuppose the authenticity of, specific theological claims or theological sources of information, in an effort to acquire a Christian understanding of (or posture toward) the natural world.
With respect to NT2, we have one rather minor refinement to offer and one quite significant observation to make. The refinement is simply that this project of attempting to acquire a distinctively Christian understanding of the natural world, which involves starting with some distinctively Christian assumptions, can quite readily be paralleled on behalf of non-Christian religious traditions. The project can be restated in a way that acknowledges this point, which we will designate NT2* (or ‘Natural Theology as a Means of Developing an Understanding of the Natural World that is Cohesive with a Particular Worldview):
NT2* (Natural Theology as a Means of Developing an Understanding of the Natural World that is Cohesive with a Particular Worldview)
The project which involves drawing upon some premises that presuppose the truth of claims made by a particular metaphysical or religious worldview, and/or invoking special cognitive abilities posited by that worldview, in an effort to acquire an understanding of the natural world that is cohesive with the central tenets of that worldview.
The observation we wish to make is this: a piece of reasoning that is an instance of NT2* can rather easily be transmuted into an instance of NT1*. Suppose we give the label ‘R’ to a piece of reasoning that is an instance of NT2*, and ‘W’ to the worldview whose tenets are being presupposed by R. The thought is that R can be turned into an instance of NT1* simply by placing it inside a conditional with the following form: if W were true, then R would be true. And yet, despite the smallness of the alteration required to turn an instance of NT2* into an instance of NT1*, this alteration makes all the difference as to whether one's reasoning yields support merely for belief in the conditional (if W were true, then R would be true) or for belief in an unconditional claim (R). For example, consider again Wright's appeal to seven features of human life that he contends find their fulfilment in the Christian story. This could be construed in either of two ways. It could be construed as an intentional effort, in the light of Christian theological assumptions, to deepen our understanding of creation and of humanity in particular. Roughly it might go like this: ‘the doctrine of human beings as created in the image of God and the doctrine of new creation are true; in light of these doctrines, we can understand these seven features of human experience as a foretaste of new creation’. This would constitute an instance of NT2*. Alternatively, Wright's reasoning could be construed as a conditional claim about what the world would be like if Christianity were true. Roughly it might go like this: ‘if Christianity were true and hence the doctrine of human beings as created in the image of God and the doctrine of new creation were true, then human experience might be expected to include these seven features as a foretaste of new creation’. This claim could then form the basis of an inference to the best explanation in favour of the truth of Christianity, which would of course be an instance of NT1*.
The relationship between the three projects
Thus far we have sought to identify several projects that commonly bear the label ‘natural theology’ and have tried to understand what is at the heart of each of them in terms of the roles that each project aims to play. We have made some refinements to two of them, suggesting that some of the limits placed on the subject matter and methods by practitioners of NT1 are arbitrary and unnecessary given the role that the project aspires to fulfil, and suggesting that NT2 need not be construed in specifically Christian terms but rather is an approach that can be adopted by practitioners of any metaphysical or religious worldview. In drawing together the foregoing discussion, we would like to make some observations about the relationship between the two projects whose descriptions we have refined and the third project, namely, natural theology as understood by Karl Barth and his followers.
The table below summarises our descriptions of the three projects, as well as taking note of what it is that allegedly makes each project both ‘natural’ and ‘theological’. One particularly interesting observation is that it is NT1*'s methodology that makes it natural but NT2*'s subject matter that makes it natural; and conversely, it is NT2*'s methodology that makes it theological and NT1*'s subject matter that makes it theological.
Having set out these characterisations of the three projects, we are well-positioned to map out the ways in which they relate to one another.
The Venn diagram in Figure 1 depicts the way in which any instance of NT1* is an instance of NT3. Further, NT1* and NT2* are mutually exclusive: nothing can be an instance of both.Footnote 30 An instance of NT2*, however, can be an instance of NT3*, as with the earlier example of the Deutsche Christen, in which some observations of the natural world (understood broadly so as to include human history) are taken together with the assumption that some specifically Christian claims are true, in order to try to deepen our understanding of God's relationship to the world. At the same time, we wonder if it is possible for something to be an instance of NT2* but not an instance of NT3*, depending upon how one interprets Barth (or the implications of Barth's theology). Some might be convinced that Barth would not have a problem with certain articulations of a ‘theology of nature’, whereby one reflects upon God's self-disclosure in Jesus in order to acquire a Christian understanding of the natural world.Footnote 31 Finally, something could be an instance of NT3 without being either an instance of NT1* or NT2*. A potential example of this might be Anselm's ontological argument in the Proslogion, given a reading of that text according to which Anselm is not trying to persuade sceptics on purportedly ‘neutral’ terms but is rather seeking after what else can be said in relation to God's existence given that we know through faith that God exists.Footnote 32 The argument, understood thus, wouldn't be an instance of NT1* because it doesn't aspire to operate on a theologically neutral playing field, but nor would it be an instance of NT2* because its subject matter is not the natural world.
Figure 1. Relationship between the three projects.
One final observation is that some projects that typically have not been considered to be natural theology of any kind might be seen, in light of our delineation and refinement of various kinds of natural theology, to constitute contributions to one or more of the three projects we have outlined. An example will help to clarify what we mean. Alvin Plantinga's watershed book Warranted Christian Belief sought to show that if Christian theism is true, then it is very likely that people can come to have knowledge of the central doctrines of Christianity without needing to rely on arguments, but rather, simply by trusting scripture and the inner witness of the Holy Spirit.Footnote 33 But doesn't this involve treating revelation as a source of properly basic beliefs? In fact, it doesn't. To be sure, Plantinga is arguing for the conclusion that the reading of scripture combined with the inner witness of the Holy Spirit can be a source of properly basic beliefs about God, the Messiah, and salvation. But our point is that the argument that Plantinga offers for this conclusion doesn't itself rely on Christian revelation; rather, it appeals to certain sorts of intuitions about the nature of knowledge, as well as intuitions about how God might set up the world so as to enable humans to acquire knowledge of God with ease. In that sense, Plantinga's project looks very much like an instance of NT1*.Footnote 34 Plantinga's project is but one example of the effort to establish some proposition about the scope of human knowledge of God, which we suggested earlier should be included in the potential areas of theological adjudication included within NT1*'s subject matter.
Conclusion
At the outset of this article, we noted that the use of the term ‘natural theology’ in the modern academy is frequently divisive and polemical, and we hope to have shown also that its use is often equivocal. In particular, the way in which Barthians use the term is apt to provoke puzzlement amongst analytic philosophers of religion, and vice versa. Moreover, the way in which analytic philosophers of religion use the term is often viewed as narrow and imperialistic by some theologians who maintain that, historically, natural theology has been understood to encompass much more than just the apologetic project of trying to establish God's existence from non-religious premises.Footnote 35 In the foregoing discussion we have tried to shed some light on these multiple misunderstandings without attempting to assert the supremacy of any one particular usage of ‘natural theology’ over any other. Because of the multifaceted and pluriform usage of the term, sweeping declarations about the enterprise of ‘natural theology’ are unhelpful. Rather, we should seek to evaluate the viability and worthwhileness of individual instances in relation to the roles that they appear to be trying to fulfil. So rather than asking whether a piece of reasoning is or isn't ‘natural theology’, we should ask what kind of natural theology it may be and how effective it is at accomplishing the aims inherent in the kind to which it belongs.
