Moderating Natural Theology: A Heuristic Interrogative Approach

Abstract

This article proposes an underappreciated value for traditional natural theology and its familiar arguments for the existence of God, without endorsing the soundness or the rational cogency of these arguments. Famously, Aquinas and Kant represent two extremes, with Aquinas endorsing some natural theology arguments for God’s existence and Kant opposing such arguments. This article recommends a moderating approach, on the grounds that while Aquinas is unduly optimistic here by the epistemic standards of many inquirers, Kant is too pessimistic regarding the heuristic value of the relevant natural theology arguments. The neglected heuristic value of these arguments, according to this article, is in their prompting in unique ways some challenging and fruitful questions for inquiry about God. The disputed natural theology arguments have not achieved anything near a consensus on their soundness or rational cogency, but they still can have significant heuristic value aside from their soundness or rational cogency. This article identifies the relevant fruitful questions and their theoretical importance for human inquiry about God. Ultimately, a heuristic interrogative approach to familiar arguments of natural theology gives these arguments a new role with resilient heuristic value for inquiry about God, even if they do not justify the belief that God exists. Such moderation, this article contends, is rationally defensible with regard to these arguments.

1. Introduction and Result

The familiar arguments of natural theology can have heuristic value for human inquiry about God, even if they fail to justify the belief that God exists. This article will explain what this value includes, using Aquinas and Kant as familiar advocates of two extremes in this area. We could consider various other advocates, but the positions of Aquinas and Kant will serve well as contrasts to this article’s central thesis. The main result will be a case for the heuristic value of some natural theology arguments regardless of the soundness or rational cogency of these arguments. This value has been unduly neglected in the relevant literature of philosophy and theology. This article begins to correct that neglect.

2. A Heuristic Approach

Kant’s famous doubts, in the Critique of Pure Reason and in the Critique of Judgement, about first-cause and teleological natural theology arguments merit attention, even though they fail to acknowledge an important lesson.1 This lesson is that the highly mixed compromising evidence underlying some natural theology arguments has value for inquiry in prompting important heuristic questions about (inquiry concerning) God and humans. For instance, why would God allow the relevant evidence to be apparently compromising regarding the moral character of God, in the manner of various arguments from natural theology?

More generally, does the evidence underlying some natural theology arguments prompt questions for humans that can illuminate (their coming to know) an important relationship between God and humans? In particular, does the evidence in question invite a choice about prioritizing one’s values in inquiry that enables a fitting response to God by leaving one suitably open and responsive to further divine evidence? Despite the difficulty of obtaining good answers, such questions will be fruitful in inquiry about God, particularly if there is, as the apostle Paul suggested, uncompromising evidence for God beyond the compromising evidence we shall identify.

The relevant heuristic questions neglected by Kant and many others include the following examples:

• What kind of qualitative experience would support the premises of the kinds of natural theological arguments supported by Aquinas, for instance, and opposed by Kant, among others? Can such experience be rationally compelling in a context of highly mixed evidence regarding God’s character or will? What would be the divine purposes in allowing for the mixed evidence about God’s reality? Would this mixed situation include divine elusiveness or hiding? If so, for what purposes? Would a divine purpose in giving self-evidence factor in the voluntary receptivity of an inquirer to the evidence for God’s reality?
• Can the relevant supporting evidence for the premises offered be purely nonpropositional or nonconceptual (free of propositional or conceptual content) and thus ‘foundational’ in not demanding further propositional or conceptual evidence? If so, what gives such foundational evidence its determinate qualitative content? Is there a potential role for divine character manifestation here (say, with moral features as virtuous ‘fruit of the Spirit’ of God), perhaps along the lines suggested by the apostle Paul in Galatians 5 (we shall return to this issue)?
• Could a self-manifested divine will figure in the kind of evidence underlying the premises of some natural theology arguments? What would such evidence look or feel like to humans in their experience? Would human conscience be affected? If so, how?
• What kind of inference from premises to conclusion, if any, could support what we find in Aquinas’s (and similar) natural theology arguments? We seem to be offered some nondeductive arguments, but of what specific kind regarding inference? Are some of the relevant arguments abductive arguments, relying on an inference to a best-available explanation? What do the details look like, especially in relation to potential defeaters and the suitable kind of explanation?

Answering such heuristic questions will refine parameters for relevant evidence and justification in relation to natural theology arguments. The answers do not come easy, as the history of controversy shows, but the questions merit careful attention for the benefit of evaluating many natural theology arguments. The questions have heuristic value regardless of the rational cogency or logical soundness of the arguments themselves. We do not need to find the arguments rationally compelling to recognize the heuristic value in the questions just raised.

The mixed and compromising evidence for God’s character in some natural theology includes evidence, although inconclusive, of some features characteristic of God: for example, an original causal role in creation and a related role as ultimate designer for aspects of the created world. Such evidence, we shall see, is highly mixed with evidence that, if reliable, compromises God’s perfect moral character. Even so, we are left with significant questions about what God’s role and our fitting response would be, in a context of such highly mixed evidence.

Here, we can find genuine value for inquiry in many natural theology arguments, even if we share Kant’s general doubts about their rational cogency. They direct us to questions that can bear important fruit for human inquiry about God. Their resilient value is in their being starting places for prompting fruitful questions regarding such inquiry, along the lines of examples 1–4 above. Such questions have heuristic value even in a mixed evidential context, including opposing instances of various kinds of evil and harmful disorder. They may lead, in addition, to the broader issue of whether agnosticism is the epistemically best response to our available evidence (I dissent from Abraham Heschel’s (1951, chp. 8) suggestion that the questions are about what is ultimately ‘ineffable’; otherwise, obvious logical problems will threaten).

One heuristic benefit for inquiry that should emerge includes our asking about what our proper relationship with God would be in inquiring about God, including with highly mixed evidence. If faced with compromising evidence regarding God’s character, we still should ask how to respond to such highly mixed evidence, for the sake of advancing our inquiry about God. We thus should ask what God would want from us in a highly mixed context of inquiry. At a minimum, God (as perfectly good) would want a positive, cooperative response to the good characteristics of God in the mixed context. Such a response can contribute to answering the question of why we are in a mixed situation of inquiry, perhaps with some opaqueness and ambiguity.

A cooperative response would have us leave room for God’s righteous self-expression and character-forming role, thus avoiding premature exclusion of God from our inquiry. A divine goal would be for humans to voluntarily accommodate the virtuous fruit of God’s Spirit in their lives of thinking, feeling, and acting, for the sake of their properly relating to God, including in conflicted contexts of highly mixed evidence. We shall illustrate such a conflicted context, without trying to settle the issue of the rational cogency of various natural theology arguments.

3. Compromising Arguments

First-cause and teleological arguments for God’s existence, developed in various forms and traditions, are favored by many advocates of natural theology. Aquinas offers such arguments with a confident conclusion that God exists; at least, that reading of Aquinas is common among his interpreters. His own arguments, however, face a problem as arguments for the God of traditional monotheism. According to many critics, they arguably support at best the existence of a lesser god, owing to their basis in highly mixed evidence that, if reliable, compromises the morally perfect character of God. We shall use Aquinas’s own first-cause and teleological arguments to illustrate this problem, but we shall not presume to settle the issue of the rational cogency of all variations on Aquinas’s arguments. This article’s heuristic approach can, and does, leave the latter issue open.

It would be rash, of course, to generalize every argument of natural theology ever endorsed. It is enough for this article to support the heuristic value of some natural theology arguments. Jürgen Moltmann (2000, pp. 68–69) has suggested a general direction for us: ‘The knowledge of natural theology is different in kind from the reasonableness of faith. Today more than ever, it takes the form of an open question rather than that of the final answer’. This article concurs with this suggestion from Moltmann.

Aquinas sums up his influential first-cause argument in the Summa Theologica:

If that by which it [something in motion ‘in the world of sense’] is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.

(I, q.2, a.3).2

• This argument considers a case of efficient causation in ‘the world of sense’, and it then affirms that nothing is either the efficient cause of itself or part of an infinite causal chain. On that basis, it concludes that there must be a first efficient cause, ‘and this everyone understands to be God’.

Let us grant for the sake of argument, despite ongoing controversy, Aquinas’s assumption that any causal chain in the sensory world is finite and thus has a first efficient cause. A serious problem with Aquinas’s argument is that his causal inference will give us, with regard to supporting evidence, at most a first cause that is just adequate for actual experienced causal chains. Such a first cause, however, falls short of a living intentional God who is worthy of worship and thus morally perfect, even when combined with Aquinas’s other natural theology arguments. The experienced causal chains are too mixed in quality, at least by the standards of many inquirers, to demand moral perfection in their source. This consideration suggests that Aquinas is too optimistic about the results of his natural theology arguments that he calls the ‘five ways’. The same holds for the following statement from the First Vatican Council in its reliance on Aquinas: “If anyone shall have said that the one true God, our Creator and our Lord, cannot be known with certitude by those things which have been made, by the natural light of human reason, let him be anathema”.3

We have, by the standards of many inquirers, no compelling reason to assign moral perfection or therefore worthiness of worship to Aquinas’s minimally adequate first cause. His proposed first cause offers no conflict with or challenge to considerable moral indifference in itself. It also emerges in a context of highly mixed evidence including evil as well as good in perceived causal chains (such as real harms as well as benefits to humans in the causal chains of the sensory world). Such highly mixed evidence challenges a straightforward inference to a single good source (or a single evil source, for that matter) for it. A much more complicated story would be needed, and it is not clear how the story should go. So, an impasse arises.

We have no good reason, on the basis of the cosmological evidence given, to ascribe to Aquinas’s first cause redemption- (or salvation-) seeking intentional agency for the overall moral benefit of humans. The latter kind of intentional agency is not required to accommodate the morally mixed data regarding the causal chains in the sensory world. These mixed data offer no definite or even highly likely indication of an intentional agent worthy of worship. P. T. Forsyth (1893, p. 100) suggests this point in remarking that ‘nature does not contain its own [moral] teleology’. It is also noteworthy that the minimally adequate first cause in question, so far as our actual evidence goes, could have ceased to exist long ago, after launching the relevant causal series. That would not fit, however, with the everlasting God prominent in traditional monotheism.

Aquinas’s first-cause argument invites controversy with its claim to a first efficient cause which ‘everyone understands to be God’ (a similarly questionable claim regarding ‘God’ occurs in his corresponding argument in Summa Contra Gentiles). Inquirers should balk at Aquinas’s reference to God here, if God is worthy of worship and thus morally perfect. The highly mixed evidence underlying the argument, in harmful as well as beneficial causal series in the natural world, does not supply the morally definite evidence needed to satisfy the demands of morally perfect intentional agency. The overall relevant evidence, taken by itself, suggests a morally mixed and compromised god at best, and this god thus does not meet a central demand of the perfectionist title ‘God’. If an argument does not enable us to affirm the existence of a morally perfect intentional agent, owing to its highly mixed and compromising evidence, it does not enable us to affirm that God (as worthy of worship) exists. Various empirical arguments of natural theology run afoul of this con0sideration, thus leaving us without adequate evidence for the existence of God (as worthy of worship). The moderating approach of this article aims to avoid this problem. It does not, however, claim or need to claim that no revision will salvage Aquinas’s general line of argument.

Aquinas endorses a teleological argument for God from perceived ‘order’, both in the Summa Theologica (I, q.2, a.3) and in the Summa Contra Gentiles (I, chp. 13, sct. 35). The latter endorsement proceeds as follows:

Discordant things cannot, always or for the most part, be parts of one order except under someone’s government, which enables all and each to tend to a definite end. But in the world we find that things of diverse natures come together under one order, and this not rarely or by chance, but always or for the most part. There must therefore be some being by whose providence the world is governed. This we call God.4

• This kind of argument faces a direct analog of the problem noted above for Aquinas’s first-cause argument.

The apparently ordered structures in nature include harmful as well as beneficial structures. Certain so-called ‘natural evils’ as well as natural ‘goods’ come to mind; meteorologists, for instance, sometimes speak of highly ‘organized’ or ‘ordered’ destructive tornadoes. So, the presumed source of the relevant structures must account for both kinds of ordered structure, the evil as well as the good. The highly mixed evidence for the structures in question thus does not confirm with definiteness the existence of the morally perfect, worship-worthy God of traditional monotheism. If God were harmful in the way some of the ordered structures in nature are, then God would be morally compromised and hence not morally perfect or worthy of worship. The God in question thus would not be the God of traditional monotheism.

For the sake of argument, we may acknowledge Aquinas’s evidence from apparent order or purpose in the sensory world. Such evidence, however, offers no conflict with or challenge to a source of the evidence that is largely morally indifferent. In addition, as suggested, it includes highly mixed evidence including good and evil in ordered structures. Aquinas has no adequate grounds in his natural theology for assigning the title ‘God’ (as morally perfect) to his supposed designer or governor of order in nature. My approach to moderating natural theology, however, does not and need not digress to the issue of whether recent variations on Aquinas’s teleological argument can escape this problem while remaining within natural theology and avoiding reliance on supernatural revelation. In any case, the well-founded ascribing of the perfectionist title ‘God’ to an intentional agent requires adequate evidence of that agent’s moral perfection, given the demand of worthiness of worship for God.

One might attempt to avoid the previous problem in Aquinas’s arguments by having natural theology include a divine ‘call’ to humans to yield to God, but this move would go beyond natural theology to supernatural theology. We may call the difficulty noted ‘the problem of highly mixed morally relevant evidence’ for Aquinas’s arguments of natural theology. The arguments in question fail to meet the need for adequate evidence for a morally perfect God who is worthy of worship. This failure raises the question of whether the highly mixed, compromising evidence from natural theology yields knowledge of God for all inquirers. It calls into question the previous claims of Aquinas and the First Vatican Council about natural theology and human understanding or knowledge regarding God. Even so, as noted, my approach to moderating natural theology leaves open the issue of whether more recent arguments of natural theology can salvage Aquinas’s general approach.

4. Beyond Compromising Evidence

The problem at hand calls for a base of suitable evidence for divine reality that is not highly mixed and compromising in the way identified. Traditional monotheists need evidence closer to the morally perfect character of God, without a compromising mixture. By way of illustration, we shall consider the epistemological position of the apostle Paul as significant for this need. This will illuminate one way to avoid the problem noted.

Paul offers the following remark pertinent to evidence of God’s reality and action:

The wrath of God is revealed from heaven against all ungodliness and injustice of those who by their injustice suppress the truth. For what can be known about God is plain to them, because God has made it plain to them. Ever since the creation of the world God’s eternal power and divine nature, invisible though they are, have been seen and understood through the things God has made. So they are without excuse, for though they knew God, they did not honor him as God or give thanks to him, but they became futile in their thinking, and their senseless hearts were darkened.

(Rom 1:18–21, NRSV, updated edition, here and in subsequent biblical translations, unless otherwise noted)

• Paul claims that God has achieved something important: ‘God has made it plain to them’, where ‘it’ is (literally) ‘what is known of God’, and ‘made it plain’ means ‘made it manifest’.

Paul explains in general how God acted to manifest God to wayward humans: ‘God’s eternal power and divine nature, invisible though they are, have been seen and understood through the things God has made’. We should clarify what Paul is not doing. As Günther Bornkamm (1969, p. 59) remarks: ‘The intention of the apostle is not to infer God’s being from the world, but to uncover the being of the world from God’s revelation; not to prove the revelation of God before the judgment of the world but to unveil the judgment of God over the world revealed in the law’.5 This consideration is made clear by Paul’s beginning with his comment that ‘God has made it plain to them’.

According to Paul, God, and not the created order by itself, has made something plain to humans, and Paul does not infer this in an argument based on nature. So, Paul does not say that either creation or ‘the things God has made’ manifest by themselves God’s reality, eternal power, or divine nature. God has self-manifested the latter ‘through the things God has made’. Paul thus does not infer God’s existence from any features of the natural world, as many natural theology arguments do. He therefore does not endorse arguments of natural theology, despite many Christian apologists reading that perspective, against our evidence, into his remarks.

We now can appreciate what Paul is doing with his previous remarks to the Roman Christians. James D.G. Dunn captures Paul’s aim:

It is Paul’s Jewish perception of the divine-human relation which remains primary: what is known of God is an act of revelation personally willed by God (v 19b) in relation to a created order (v 20); and man is recognized as a responsible agent in face of this revelation, so that his failure to respond appropriately is not simply a lack of perception, a defect in spiritual capacity, but a moral failure, a culpable act, ‘without excuse’ (v 20b).

(Dunn 1988, p. 71)

• Dunn rightly notes that Paul’s remarks begin with an endorsement of God’s revelation as what makes God known (‘God has made it plain to them’). In addition, Paul sets this revelation in the context of ‘a created order’. A key issue concerns what part(s) of creation the revelation involves. We need to clarify this in the light of Paul’s remarks in their context, without imposing extraneous philosophical assumptions.

We have noted two natural theology arguments from Aquinas that, by themselves, rest on evidence that arguably compromises the moral character of God. Paul avoids such evidence by focusing on evidence shown by God regarding ‘God’s eternal power and divine nature, invisible though they are’. What of this divine power and this divine nature? What kind of experience underlies Paul’s endorsement of them, as a result of God’s ‘showing’ them? A principle of charity requires that we not ascribe an obviously bad inference to Paul here, as if the sensory world of nature by itself shows ‘God’s eternal power and divine nature’. Paul nowhere suggests such a dubious inference, even if some Christian apologists do.

Although overlooked by many interpreters, Paul’s larger context of remarks in his epistle can save us from distorting him with the promotion of compromising evidence. We receive direction from Paul in connection with two passages from his epistle on how God presents evidence to humans. The first passage continues with Paul’s concern in Romans 1 about human accountability to God: ‘Do you despise the riches of his kindness and forbearance and patience? Do you not realize that God’s kindness is meant to lead you to repentance?’ (Rom 2:4). Paul regards the latter repentance as a desired means to human reconciliation to God, courtesy of receiving divine mercy as grace toward humans (Rom 5:10–11, 15–17, 2 Cor 5:18–21).

In a different context, Paul acknowledges his facing perplexity, including pressing questions, and he attributes to it a divine purpose: ‘We have this treasure in clay jars, so that it may be made clear that this extraordinary power belongs to God and does not come from us’ (2 Cor 4:7). We shall see how some questions can have heuristic value toward recognizing divine power at work in human experience.

Paul has nothing to say, in his epistle to the Romans or elsewhere, about morally thin indicators of either a first cause for nature or a designer for ‘order’ in the sensory world. As James Barr (1993, p. 47) notes: ‘Paul says nothing about the order of the cosmos as a basis on which to found the knowledge of God’. Instead, although Barr and most other interpreters miss this important point, Paul considers God’s presentation of divine kindness and goodness to humans as intended to lead them to repentance in their turning to honor God as their Lord. Such kindness self-manifests God’s moral character to humans, sometimes directly, and it thus does not rely on the kind of broad compromising evidence noted previously in connection with Aquinas’s arguments. Divine kindness can be manifested ‘through the things God has made’, as suggested by Paul, including through contexts of nature that are beneficial to humans. So, we lack a basis to attribute to Paul concerns about a first cause or a designer for nature in general. The actual context of his remarks makes this clear, despite widespread neglect of this fact.

Paul continues his explanation of relevant divine evidence when he explains why faith and hope in God do not ‘disappoint’ the people of God regarding evidential support. He writes: ‘Hope [in God] does not put us to shame, because God’s love has been poured into our hearts through the Holy Spirit that has been given to us’ (Rom 5:5). Paul would say the same about faith in God (mentioned in Rom 5:1): We need not be ashamed or disappointed about faith or hope in God, because God has offered to receptive humans due supporting evidence in a character trait of God revealed to them: unmatched divine love for them (and others). If we read Paul to speak of God’s self-revealing or self-manifesting evidence for divine reality ‘in’ people (a live option for his use of ‘en’ in Rom 1:19), we can easily accommodate the role, in Romans 5:5, of divine love revealed in the ‘heart’ or conscience of a human (see Romans 2:15, 9:1 on Paul’s evidently interchangeable use of ‘conscience’ and ‘heart’).

Divine love, in Paul’s thinking, heads a list of divine character traits he calls ‘the fruit of the Spirit’. He writes to the Galatian Christians: ‘The fruit of the Spirit is love, joy, peace, patience, kindness, generosity, faithfulness, gentleness, and self-control. There is no law against such things. If we live by the Spirit, let us also be guided by the Spirit’ (Gal 5:22–23, 25). Paul holds that such traits are moral features manifesting God’s moral character (see Dunn 1993), particularly God in action as the Spirit of God, and thus that they are moral realities by which God leads, or guides, the people of God. When those personality traits come into a person’s experience, according to Paul, God comes to that experience to lead the person to God to comply with God. Thus, ‘All who are led by the Spirit of God are children of God’ (Rom 8:14).

The traits in question, Paul holds, are realities whereby ‘it is God who is at work in you, enabling you both to will and to work for his good pleasure’, and by which people are to ‘work out your own salvation with fear and trembling’ (Phil 2:12–13). These traits are not abstract platonic forms or concepts; instead, they are intentional moral features of God that aim to lead people toward God (and God’s will) in their moral struggles, including in conscience. The intervention of these traits in a person’s experience seeks to hold that person accountable to God, in order to be conformed to God’s moral character. Attention to them can bring recognition of one’s being challenged and even nudged, uncoercively, in an intentional manner toward what is truly good, in relation to God. This intentional feature indicates a personal agent at work in the leading, including in a morally challenged and nudged human conscience.

The evidence from divine moral character traits, in the fruit of the Spirit, is not compromising or highly mixed in the way the evidence offered above by Aquinas is. It is, unlike Aquinas’s evidence, suitably focused to indicate, if fallibly and partially, the actual moral character of a God who is worthy of worship and thus morally perfect. It thus can be indicative of God, without an argument hampered by compromising evidence. The evidence of God from the fruit of the Spirit is not an argument at all, as it does not include or rest on premises and an inferred conclusion. Moral character traits are not arguments but, when manifested, they can be evidence, indicators of reality, nonetheless.6 We thus should not confuse evidence of God’s reality with arguments for God’s reality.

God would have the freedom to self-present evidence for divine reality and goodness without presenting arguments for them. Divine self-manifestation is a live option, acknowledged by Paul and the book of Isaiah: ‘I have shown myself to those who did not ask for me’ (Rom 10:20; cf. Isa 65:1). Paul holds that God shows himself to humans in the manifested moral character traits that are the fruit of God’s Spirit. Humans can turn away, focusing on something else, but this can entail missing an opportunity to be morally challenged and benefited by God in formation of their moral character. If God seeks moral character formation in humans, as central to their redemption or salvation, the manifestation of divine moral traits to them would be not only a fitting source of evidence of divine reality and goodness but also a guide to moral character-formation. This approach illustrates an alternative that avoids the problem noted above for Aquinas’s natural theology.

5. Whither Natural Theology?

Even if Paul does not rely on any familiar argument of natural theology, does the position just ascribed to him qualify as natural theology? An answer will illuminate the focus of this article, but we should not answer without a clear statement of what natural theology is. If natural theology is just theology not relying on scriptural or other propositional revelation from God, then Paul’s evidence from the virtuous fruit of the Spirit qualifies as natural theology. The fruit of the Spirit can be presented to a person’s awareness without reliance on scriptural or other propositional revelation. If, however, natural theology is stricter, disallowing any direct role for God in its foundational, noninferential evidence, then Paul is not endorsing natural theology, let alone an argument of natural theology. Paul does acknowledge, however, a role for God in the foundational evidence of divine reality and goodness in the fruit of the Spirit. This is no defect in Paul, but it is a reality in his perspective on evidence of God’s reality, without reliance on any argument of natural theology.

James Barr understands ‘natural theology’ to mean that ‘‘by nature’ (that is, just by being human beings), men and women have a certain degree of knowledge of God and awareness of him … and this knowledge or awareness exists anterior to the special revelation of God made through Jesus Christ, through the Church, through the Bible’ (Barr 1993, p. 1). The lack of clarity in ‘by nature’ prevents us from applying this approach to Paul. If ‘by nature’ entails ‘apart from God’s revelation’, Paul would dissent, on the aforementioned grounds that God shows himself to humans as the basis of their accountability to and knowledge of God. Even if this revelation of God is not through Jesus, the Church, or the Bible, it still is, according to Paul, a revelation from God. Paul does mention the Gentiles doing ‘by nature’ (phusei) the things of the law (Rom 2:14), but this is not a claim to their knowing God (the latter point is not given due attention by Barr 1993).

Paul takes the presented fruit of the Spirit to figure in evidence that holds some people accountable to God and even enables his talk of their ‘knowing God’, in a sense involving their accountability to God on the basis of evidence from God. For instance, he writes of people who ‘by their injustice suppress the truth’ (about God): ‘Though they knew God, they did not honor him as God or give thanks to him, but they became futile in their thinking, and their senseless hearts were darkened’ (Rom 1:21). How did they ‘know God’? Clearly not by the kind of speculative arguments and compromising evidence invoked above by Aquinas. Paul shows no sign of endorsing that kind of inferential approach, even if some Christian apologists try to read him that way. Instead, Paul maintains that God’s Spirit self-manifests divine moral personality traits to some humans, via the fruit of the Spirit, and this holds them to an accountable response, a response that may ‘suppress the truth’ regarding divine intervention. They thus ‘know God’ by virtue of morally relevant evidence of God’s intervening moral character in their experience.

Paul, contrary to some Christian apologists, does not make the mistake of claiming that knowing God is universal among humans. He writes to the Galatian Christians: ‘Formerly, when you did not know God, you were enslaved to beings that by nature are not gods. Now, however, that you have come to know God, or rather to be known by God, how can you turn back again to the weak and beggarly elemental principles?’ (Gal 4:8–9). So, Paul denies that all people know God, in the absence of their ‘coming to know God’. Exactly how they come to know God is, as expected, a matter of controversy among interpreters of Paul.

Paul emphasizes to the Galatian and Corinthian Christians that their coming to believe in and know God depends on God’s intervening Spirit (Gal 3:3–5, 1 Cor 2:4–5, 4:10–12), including the fact that ‘God has sent the Spirit of his Son into our hearts, crying, “Abba! Father!”’ (Gal 4:6; cf. Rom 8:15–16). This is the divine Spirit who self-manifests God to humans in manifesting the fruit of the Spirit as God’s moral personality traits (Gal 5:22–23). Humans, however, can ‘quench’ this Spirit by turning away from the character-forming fruit of that Spirit (1 Thess 5:19). In doing so, they voluntarily reject ‘knowing God’ as their guiding Lord. This is a rejection of lordship knowledge of God whereby a person yields volitionally to God’s unique character. This person still could have thinner accountability knowledge of God as simply knowing one’s responsibility to God in the wake of divine challenges in moral experience. The latter accountability knowledge does not entail the former, morally more robust lordship knowledge.

Paul’s approach to knowledge of God enables us to identify a shortcoming in Kant’s influential moral perspective on practical, as opposed to theoretical, knowledge of God.7 Kant’s role for God in morality falls short of Paul’s perspective on divine self-manifestation in moral experience. Kant (1979, p. 159) has a role for divine commands, including ‘eternal and unchangeable laws’, in the moral motivation of humans, but this role omits an evidentially foundational role in human experience for the self-manifestation of God’s intentional moral character and its moral fruit directed toward righteousness for humans. Without such a self-manifestation in morally qualitative directedness for humans, Kant’s theism will lack the needed evidence for the authenticity of its assumed ‘eternal laws’ in motivation—that is, for their coming from God. It will lack the kind of evidence needed for a purposive, intentional God seeking to share divine righteousness among humans. The result will be an evidential deficiency regarding the God described by Paul.

John Baillie has identified a relevant shortcoming in Kant’s moral perspective on God.

[Kant] taught that [moral] guidance is originally revealed to us in the form of a self-evidencing law—a mere obligation detached, as it were, from him [God] who lays the obligation upon us; and that the knowledge of him who thus obliges us is afterwards reached as an inference from the felt nature of the obligation. We, on the other hand, have argued that the Source of the obligation is himself directly revealed to us and that it is in this vision of his glory and his holiness that our sense of obligation is born. It is his perfection that rebukes us; it is his love that constrains us. Hence it is no mere law that is revealed to us, but a living Person.

(Baillie 1939, p. 162)

• Baillie thus proposes that the evidence for God in human moral experience is more direct than Kant held. Baillie (1929, pp. 132–33) notes: ‘It is not merely that through our values we reach God or that from them we infer Him, but that in them we find him’. The directness of divine evidence in human moral experience acknowledged by Baillie fits better than Kant’s position with the epistemological perspective of Paul. It preserves the divine intentional and thus person-centered character of such evidence that Kant’s perspective puts at risk with its focus on laws without corresponding experienced divine intentionality.

6. Questioning God and Ourselves

We return to a divine goal of lordship knowledge for humans, going beyond mere accountability knowledge and mere factual knowledge that God exists. In the context regarding knowing from the perspective of God’s new creation, Paul highlights the centrality of lordship knowledge in his preaching of Jesus as Lord (2 Cor 4:5, 5:16–17). Such knowledge exceeds what Aquinas and Kant had in mind in their theoretical and practical arguments regarding God. It includes an intentional Lord seeking a direct response to God via conformity to God’s will to some degree. It thus includes one (divine) will challenging another (human) will, whereby a human experiences a good but morally challenging will firsthand. This is an I–Thou context of volitional encounter that needs no argument for its effectiveness or apprehension, let alone a philosophical argument in the tradition of Aquinas’s five ways. Paul thinks of human conscience as a context where such an encounter can occur with good effect (Rom 9:1).

Despite their compromising evidence, some arguments of natural theology can present enough evidence of God’s reality to prompt the question of whether we should, as responsible inquirers, seek and attend to further, improved evidence of God in our experience. The latter question should encourage our questioning ourselves regarding our fitness to discern God’s reality and goodness independently. If we refuse such questioning about ourselves, we should ask why we do so. Are we cognitively presumptuous regarding discerning and receiving evidence regarding God? If so, we should redirect ourselves for the sake of responsible inquiry about God. The questions we value and consider reflect our status as responsible inquirers, and our blind spots in inquiry can emerge as a result. We can effectively counter our blind spots only if we recognize them and intend to challenge them. Our intentions in inquiry matter here.

God, being perfectly good, would care how we inquire about God. That is, God would care about our attitudes and motives in inquiry. If our aim is to ‘believe what is true’, regardless of our moral intentions in doing so, God may seek a better aim in us. Jesus remarked that ‘the pure in heart’ will see God (Matt 5:8), and his suggestion is that only the pure in heart will do so. This theme echoes some of the Jewish scriptures, and it assumes that God does not sacrifice righteousness for merely intellectual inquiry in theology, particularly inquiry about God’s reality and goodness.

A divine aim would be that inquirers become willing not only to receive the fruit of the Spirit but also to attend to and honor it as the intentional work of God in their lives. It thus would call for a new way of looking at their relevant evidence of God, as evidence of God intentionally working in their moral experience for their lasting benefit. In this context, humans could gain a moral rapport with God, whereby they are guided by and responsive to God. The relevant evidence thus would come to fruition in moral interactions between God and humans, leading to their cooperation with God. In that case, humans benefit from God being their recognized guide and provider, including in a context of receiving evidence and inquiring about God. This is not surprising if God works by self-manifestation in the cognitive and moral guidance of humans. As a result, humans could come to recognize themselves to be recipients of God in their evidence and inquiry about God. They also could come to understand that God allows the highly mixed evidence in order to provide them with an actual opportunity for receiving needed divine guidance in the midst of such evidence. It thus could highlight the value of God and divine guidance even in inquiry about God.

A critic might propose that we simply dispense with the natural theology arguments in question, on the grounds that they fail to justify (in any adequate way) belief that God exists. Otherwise, so the proposal goes, we will be susceptible to tolerating all kinds of dubious arguments. In addition, the critic could allege, we can come by the allegedly fruitful questions in inquiry without valuing the arguments in dispute. I have suggested, however, that such a proposal would be premature. One consideration is that we actually have the natural theology arguments under consideration, and they do prompt heuristic questions valuable to inquiry about God (as illustrated above), even given their alleged evidential shortcomings. The latter value for inquiry is not challenged by suggesting that there are other sources of the same value. In addition, we evidently have no resources to show that the arguments in dispute lack the heuristic value identified. A rough analog from the natural sciences is also noteworthy. Arguments for string theory in physics face highly mixed evidence and are thus inconclusive, but they remain fruitful for inquiry in physics, including from the standpoint of assessing relevant evidence. It would be epistemically ill advised, then, to dispense with them as devoid of heuristic value in inquiry.8

Human dependence on God for foundational evidence and effective inquiry about God is not a circular argument, because foundational evidence from God is not an argument for God at all. Instead, we are considering a supervisory divine roll in humans’ receiving and recognizing evidence from God. In the end, God actively shows God to some humans at times, according to Paul’s perspective. Paul thus stresses as a priority humans not only knowing God but ‘being known by God’ (Gal 4:9, 1 Cor 8:2), having been sought by God to be conformed to God’s moral character. Human conformity to God’s moral character is not fully realized now, but its beginning now could supply an evidential voucher or down payment to some receptive inquirers for its full realization later, in the fullness of time (2 Cor 1:22). In that case, the process is eschatological, awaiting completion in the future.

Although argument is not crucial to the reality of foundational evidence from God in human experience, it still can play a role in inquiry about God. Given suitable moral experience, people can benefit from inference to a best-available explanation, or abduction,9 in presenting evidence from the manifested fruit of the Spirit (this is not to be confused with simply having such evidence, which is a separate topic). If the best available explanation of this fruit for a person includes a causally influential role for divine guidance toward righteousness, in the absence of undermining considerations, that person will have a responsible epistemic means of presenting the evidence in question. Various parts of the sciences present evidence with such explanatory support, and nothing in principle bars a similar approach for morally relevant religious experience in the present context. Even so, this is not a means of rescue for the rational cogency or soundness of the aforementioned questionable arguments of traditional natural theology.

The best-available explanation can, and does, vary relative to differing evidence among persons, and this holds for the sciences as well as religious experience. Even so, some people find that their experience of the relevant fruit of the Spirit is evidently intentional in a manner suited to their receiving divine guidance toward righteousness. They thus may offer an abductive inference to present their evidence in question. I submit that we have no way to rule out the viability of that prospect for all inquirers, and that it merits careful attention for the sake of elucidating human moral experience, including in relation to God. Giving it such attention can contribute to paying serious attention to the kind of perspective we have identified in Paul. Kant’s pessimism about divine evidence (of a cognitively relevant sort) did not give due attention to such an explanatory prospect.

God, we have suggested, could take the initiative by giving self-evidence that prompts human inquiry, and humans would be expected to respond with responsible and valued handling of that evidence. Such handling includes discerning that evidence to be good and choosing to value it aright, while raising questions about it that open us to divine guidance toward its benefits. This consideration fits with the general lesson of the following biblical challenge: ‘I call heaven and earth to witness against you today that I have set before you life and death, blessings and curses. Choose life so that you and your descendants may live’ (Deut 30:19). This article’s approach to inquiry about God instantiates that lesson in a way that restores a voluntary human role in inquiry regarding some otherwise seemingly dispensable arguments of natural theology.10

We can now see how some biblical writers can appear to endorse a confident natural theology. For instance:

• The heavens are telling the glory of God,
• and the firmament proclaims his handiwork.
• Day to day pours forth speech,
• and night to night declares knowledge.
(Psalm 19:1–2)

• This psalm suggests that the psalmist has lordship knowledge of God in the sense noted above (in, for instance, verse 14: ‘Let the words of my mouth and the meditation of my heart be acceptable to you, O Lord, my rock and my redeemer’). So, the psalmist is not in an evidential vacuum as a neutral observer of ‘the heavens’ or of nature in general.

The psalmist brings a prior lordship knowledge of God, and this knowledge contributes to what he attributes to the heavens. In particular, he does not insist that ‘the heavens’ alone declare the glory of God without God’s showing forth that glory. So, there is no need to take the psalmist to exclude or to bracket his prior lordship knowledge (and corresponding evidence) of God’s reality and goodness.

7. Conclusions

Kierkegaard (1948) proposed that purity of heart is to will one thing, and that may be part of the reality we face in inquiry about God. Purity of heart in inquiry, however, may also include discerning how God self-reveals to humans, including with the fruit of the Spirit of God. Natural theology typically overlooks a central role for the fruit of the Spirit, but that is a problem for natural theology, not for how God self-reveals. If humans need divine help in their discerning God’s reality, that should be accommodated by an approach to coming to know God. Even so, natural theology can contribute something of genuine value to humans coming to know God. It can do so, we have seen, by prompting important heuristic questions about human inquiry regarding God, and these questions can lead to improved recognition of the kind of evidence God would offer to humans. Even if this is an instrumental value for some natural theology in inquiry about God, it is genuine value nonetheless. As a result, we may now consider some natural theology to have heuristic value for inquiry about God, even if it fails to justify belief that God exists.11