Natural Theology: Its Scope and Limits
Natural Theology: Its Scope and Limits
We now turn to consider the important question of the manner and extent to which God may be known through the natural order. This important area of theological debate is traditionally known as “natural theology” and has assumed increased importance in recent years on account of the growing interest in promoting dialogue between Christian theology and the natural sciences. Might the study of the natural world lead to an increased appreciation of its creator?
“The heavens declare the glory of God; the heavens proclaim the work of God's hands” (Psalm 19: 1). This well-known text can be seen as representing a general theme within the Christian Bible – that something of the wisdom of the God who made the world can be known through the world that was created. The exploration of this theme has proved to be one of the most fruitful areas of theology.
Traditionally, natural theology is understood (especially by philosophers of religion) to refer to what can be known of God through the natural world, without any divine guidance or revelation. In his major study Perceiving God (1991), the American philosopher of religion William P. Alston (1921–2009) defines natural theology as “the enterprise of providing support for religious beliefs by starting from premises that neither are nor presuppose any religious beliefs.” In traditional Catholic thought, natural theology clears the ground for revealed theology, pointing to the existence and something of the character of God, without disclosing such mysteries as the Trinity or incarnation.
There has been considerable disagreement within Christian theology over both the definition and merits of “natural theology.” Six main approaches can be distinguished within the western theological tradition. These are not mutually inconsistent, and it is common to find theologians adopting more than one of these approaches.
We begin our discussion of natural theology by considering what is widely regarded as a landmark in this matter: the contribution of Thomas Aquinas, which has been particularly influential in Catholic theology.
Thomas Aquinas (c.1225–74) on Natural Theology
The doctrine of creation is of central importance to a classic approach to the concept of natural theology. This is perhaps best seen in what is widely regarded as one of the greatest texts to address this theme: Thomas Aquinas's Summa contra Gentiles (“Summary against the Gentiles”), written during the period 1259–61, initially at Paris and subsequently at Naples. One of its most significant discussions concerns the manner in which God may be understood to be related to the creation – a relationship which Aquinas analyzes in terms of causality, as follows.
For Aquinas, there exists a fundamental “likeness [similitudo] to God” within the created order as a consequence of God being the cause, in some sense of the word, of all created things. In that no created thing can be said to come into existence spontaneously, the existence of all things can be considered to be a consequence of a relationship of causal dependence between the creation and its creator. Using what are essentially Aristotelian categories of causality, Aquinas sets out a position which we may summarize as follows:
The full argument set out by Aquinas is complex and not without its difficulties; nevertheless, its conclusion is clear. There are, so to speak, physical or metaphysical fingerprints within what is caused which provide the basis for an inductive argument to the existence of that cause and allow at least some aspects of its nature to be established. If God made the world, God's “signature” (so to speak) may be found within the created order. Aquinas puts this point as follows:
Meditation on [God's] works enables us, at least to some extent, to admire and reflect on God's wisdom. [...] We are thus able to infer God's wisdom from reflection upon God's works. [...] This consideration of God's works leads to an admiration of God's sublime power, and consequently inspires reverence for God in human hearts. [...] This consideration also incites human souls to the love of God's goodness. [...] If the goodness, beauty, and wonder of creatures are so delightful to the human mind, the fountainhead of God's own goodness (compared with the trickles of goodness found in creatures) will draw excited human minds entirely to itself.
Something of the torrent of God's beauty can thus be known in the rivulets of the beauty of the creation.
For Aquinas, one of the most fundamental qualities that are to be attributed to God is that of “perfection.” Although this concept can clearly be understood in moral terms, Aquinas uses it to characterize the distinctiveness of God in respect of the created order. “Perfection” is a quality which is possessed by God, and is possessed by that which God has created:
In this sense, “perfection” may be thought of as an attribute which is characteristic of God but which is reflected in the created order on account of the metaphysically primary relationship of God to all other things.
Subsequent Catholic approaches to natural theology have built upon, refined, or qualified the position first articulated by Thomas Aquinas. The First Vatican Council's “Dogmatic Constitution on the Catholic Faith” (1870) laid it down as a matter of faith that God has revealed himself in two ways, naturally and supernaturally:
Holy mother Church holds and teaches that God, the beginning and end of all things, can certainly be known by the light of natural human reason from created things: “his eternal power and divine nature, invisible though they are, have been understood and seen through the things he has made” (Romans 1: 20); nevertheless, it has pleased his wisdom and goodness to reveal himself and the eternal decrees of his will to the human race in another and supernatural way.
Two points of particular importance emerge from these later discussions. First, the recognition of a legitimate role for natural theology does not mean that reason has replaced faith. Nor does it mean that philosophical reflection has displaced the grace of God revealed in Christ. Faith and grace remain primary for all believers. Natural theology, however, offers the opportunity to establish certain truths by means common to all persons. It plays an important apologetic role. It is important to remember in this respect that Thomas Aquinas's Summa contra Gentiles is thought to have been written partly in order to help Islamic readers gain an understanding of Christian faith through shared beliefs based on reason.
Second, whatever can be known of God through nature is not to be taken as the “grounds” or “foundations” of additional, revealed truths. Many Catholic theologians are inclined to recognize a continuum between natural theology (that which is known of God by the light of natural reason) and revealed theology (that which is known by the light of faith). In contrast, many Protestants tend to accentuate the distinctiveness of natural and revealed knowledge of God at this point.
With this point in mind, let us turn to a classic Protestant account of natural theology, developed in the sixteenth century by John Calvin.
John Calvin (1509–64) on Natural Theology
The first book of Calvin's influential Institutes of the Christian Religion (1559) opens with an important discussion of how we can know anything about God. Calvin affirms that a general knowledge of God may be discerned throughout the creation – in humanity, in the natural order, and in the historical process itself. Two main grounds of such knowledge are identified: one subjective, the other objective. The first ground is a “sense of divinity” (sensus divinitatis) or a “seed of religion” (semen religionis), which has been planted within every human being by God. God has endowed human beings with some inbuilt sense or presentiment of the divine existence. It is as if something about God has been engraved in the heart of every human being. Calvin identifies three consequences of this inbuilt awareness of divinity: the universality of religion (which, if uninformed by the Christian revelation, degenerates into idolatry), a troubled conscience, and a servile fear of God. All of these, Calvin suggests, may serve as points of contact for the Christian proclamation. The second such ground lies in experience of, and reflection upon, the ordering of the world. The fact that God is creator, together with an appreciation of the divine wisdom and justice, may be gained from an inspection of the created order, culminating in humanity itself.
It is important to stress that Calvin makes no suggestion whatsoever that this knowledge of God from the created order is peculiar to, or even restricted to, Christian believers. Calvin is arguing that anyone, by intelligent and rational reflection upon the created order, should be able to arrive at the idea of God. The created order is a “theater” or a “mirror” for the displaying of the divine presence, nature, and attributes. Although invisible and incomprehensible, God wills to be known under the form of created and visible things, by donning the garment of creation.
There is within the human mind, and that by natural instinct, a sense of divinity. This we take to be beyond controversy. [...] There are innumerable witnesses in heaven and on earth that declare the wonders of his wisdom. Not only those more arcane matters for the closer observation of which astronomy, medicine, and all of natural science are intended, but also those which force themselves upon the sight of even the most unlearned and ignorant peoples, so that they cannot even open their eyes without being forced to see them.
Calvin thus commends the natural sciences (such as astronomy and medicine) on account of their ability to illustrate further the wonderful ordering of the creation, and the divine wisdom which this indicates. Significantly, however, Calvin makes no appeal to specifically Christian sources of revelation at this point. His argument is based upon empirical observation and reasoning. If Calvin introduces scriptural quotations, it is to consolidate a general natural knowledge of God rather than to establish that knowledge in the first place. There is, he stresses, a way of discerning God within creation which is common to those inside and outside the Christian community.
Having thus laid the foundations for a general knowledge of God, Calvin stresses its shortcomings; his dialogue partner here is the classical Roman writer Cicero (106–43 bc), whose On the Nature of the Gods is perhaps one of the most influential classical expositions of a natural knowledge of God. Calvin argues that the epistemic distance between God and humanity, already of enormous magnitude, is increased still further on account of human sin. Our natural knowledge of God is imperfect and confused, even to the point of contradiction on occasion. A natural knowledge of God serves to deprive humanity of any excuse to ignore the divine will; nevertheless, it is inadequate as the basis for a fully fledged portrayal of the nature, character, and purposes of God.
Having stressed this point, Calvin then introduces the notion of revelation. Scripture reiterates what may be known of God through nature, while simultaneously clarifying this general revelation and enhancing it. “The knowledge of God, which is clearly shown in the ordering of the world and in all creatures, is still more clearly and familiarly explained in the Word.” It is only through Scripture that the believer has access to knowledge of the redeeming actions of God in history, culminating in the life, death, and resurrection of Jesus Christ. For Calvin, revelation is focused upon the person of Jesus Christ; our knowledge of God is mediated through him. God may thus be fully known only through Jesus Christ, who may in turn be known only through Scripture; the created order, however, provides important points of contact for and partial resonances of this revelation.
The basic idea here, then, is that a knowledge of God the creator may be had both through nature and through revelation, with the latter clarifying, confirming, and extending what may be known through the former. Knowledge of God the redeemer – which for Calvin is a distinctively Christian knowledge of God – may only be had by the Christian revelation, in Christ and through Scripture.
The Renaissance: God's Two Books
One of the most interesting ways of correlating natural and revealed theology became particularly influential at the time of the Renaissance. The metaphor of “God's two books” was used to indicate how nature and the Bible could be brought into a creative conversation. The “book of nature” was seen as indicative of God, while the “book of Scripture” was seen as providing this with greater intellectual substance, leading to salvation, not simply enhanced understanding. The Belgic Confession (1561) uses this framework in affirming that knowledge of God can come about by two quite different means:
First, by the creation, preservation, and government of the universe, which is before our eyes as a most beautiful book, in which all creatures, great and small, are like so many characters leading us to contemplate the invisible things of God, namely, his eternal power and Godhead, as the Apostle Paul declares (Romans 1: 20). All of these things are sufficient to convince humanity, and leave them without excuse. Second, he makes himself known more clearly and fully to us by his holy and divine Word; that is to say, as far as is necessary for us to know in this life, to his glory and our salvation.
The two key points made here are:
During the seventeenth century, the “two books” model gained wider cultural traction. Nature and Scripture came to be seen as two distinct yet complementary sources for a knowledge of God. Francis Bacon (1561–1626) commended the study of both the “book of God's word” and the “book of God's works” in his Advancement of Learning (1605). In his 1674 tract The Excellency of Theology Compared with Natural Theology, Robert Boyle (1627–91) noted that “as the two great books, of nature and of scripture, have the same author, so the study of the latter does not at all hinder an inquisitive man's delight in the study of the former.” At times, Boyle referred to the world as “God's epistle written to mankind.” Similar thoughts can be found expressed in the 1643 classic of Sir Thomas Browne (1605–82), Religio medici (“The Religion of a Physician”):
There are two books from whence I collect my divinity. Besides that written one of God, another of his servant, nature, that universal and publick manuscript, that lies expansed unto the eyes of all. Those that never saw him in the one have discovered him in the other.
This metaphor of the two books with the one divine author was of considerable importance in holding together Christian theology and piety and the emerging interest and knowledge of the natural world in the seventeenth and early eighteenth centuries, and continues to be used today.
Eastern Orthodoxy on Natural Theology
Discussions of natural theology within the Christian tradition are often dominated by western voices. Yet it is important to note that the Orthodox tradition has developed a distinct approach to natural theology, which echoes at points some themes of the “two books” model. Basil of Caesarea (c.330–79), for example, emphasized how human beings naturally intuit God from the created order:
We were made in the image and likeness of our Creator, endowed with intellect and reason, so that our nature was complete and we could know God. In this way, continuously contemplating the beauty of creatures, as if they were letters and words, we could read God's wisdom and providence over all things.
The Orthodox emphasis on God's creating the world in a “rational” manner is of importance. Human rationality reflects the “image of God” and is able to grasp something of the nature of God from the work of creation. Where some later medieval theologians tended to emphasize the distinction between the “natural” and “supernatural” orders, Orthodoxy has always seen the fundamental distinction as being between the creator and the creature. Orthodoxy holds that it is thus legitimate to speak of “natural revelation” and “supernatural revelation,” and to see the latter as fulfilling the former. It generally rejects any scholastic or modernist tendency to ignore divine influence on human theological reflection on the world, as if humanity were unaided by God in this process of reflection.
The Romanian Orthodox writer Dumitru Stăniloae (1903–93) is an excellent representative of this tradition. In his Dogmatic Theology, originally published in Romanian in 1978, Stăniloae highlights the major themes of an Orthodox approach to natural theology:
The Orthodox Church makes no separation between natural and supernatural revelation. Natural revelation is known and understood fully in the light of supernatural revelation. [...] Supernatural revelation merely restores direction toand provides a more determined support for that inner movement maintained within the world by God through natural revelation. [...] Consequently supernatural revelation places natural revelation itself in a clearer light.
The Barth–Brunner Debate (1934)
For many, the landmark debate over natural theology was the 1934 exchange between the two Reformed Protestant theologians Karl Barth (1886–1968) and Emil Brunner (1889–1966). Karl Barth was noted for his early hostility toward any idea of natural theology. For Barth, “natural theology” represented a concerted human attempt to subvert revelation by declaring that what needs to be known about God can be determined without recourse to divine self-disclosure. Barth's hostility toward natural theology thus rested on his fundamental belief that it undermined the necessity and uniqueness of God's self-revelation. If knowledge of God can be achieved independently of God's self-revelation in Christ, it follows that humanity can dictate the place, time, and means of its knowledge of God.
For Barth, there is a close link between natural theology and the theme of human autonomy. As Barth understands the concept, natural theology affirms and expresses the human desire to find God on our own terms. Natural theology thus appears to posit a second source of revelation alongside Jesus Christ. For Barth, revelation is only to be had through God, as a consequence of God's gracious decision that God wishes to be known. There is no manner in which God can be known outside and apart from God's self-revelation.
Some were alarmed by this suggestion. What of those biblical passages which pointed toward some kind of natural knowledge of God, such as Romans 1: 19–20, which speaks of the invisible things of God being known through the created order? And what of Calvin's recognition of a natural knowledge of God? Surely a Reformed thinker like Barth should take his own tradition seriously? Emil Brunner was one of several Reformed theologians in the 1930s to express misgivings about Barth's negative assessment of natural theology.
In 1934, Brunner published a short work entitled Nature and Grace. In this work, he argued that “the task of our theological generation is to find a way back to a legitimate natural theology.” Brunner located this approach in the doctrine of creation, specifically the idea that human beings are created in imago Dei, “the image of God.” Human nature is constituted in such a way that there is an analog with the being of God. Despite the sinfulness of human nature, the ability to discern God in nature remains. Sinful human beings remain able to recognize God in nature and in the events of history, and to be aware of their guilt before God. There is thus a “point of contact” (German: Anknüpfungspunkt) for divine revelation within human nature.
Brunner had used this idea of the “point of contact” back in 1927, and it is integral to his understanding of human nature. For Brunner, human nature is constituted in such a way that there is a ready-made point of contact for divine revelation. Revelation thus addresses itself to a human nature which already has some idea of what that revelation is about. For example, take the gospel demand to “repent of sin.” Brunner argues that this makes little sense unless human beings already have some idea of what “sin” is. The gospel demand to repent is thus addressed to an audience which already has at least something of an idea of what “sin” and “repentance” might mean. Revelation brings with it a fuller understanding of what sin means – but, in doing so, it builds upon an existing human awareness of sin.
Barth believed that Brunner's positive evaluation of natural theology seemed to imply that God needed help to become known, or that human beings somehow cooperated with God in the act of revelation. “The Holy Spirit [...] needs no point of contact other than that which that same Spirit establishes.” For Barth, there was no “point of contact” inherent within human nature. Any such “point of contact” is itself the result of divine revelation. It is something evoked by the Word of God, rather than something that is a permanent feature of human nature. Barth had begun to have misgivings about Brunner's more “dialogical” approach to revelation in the late 1920s, and had already come close to severing their relationship in 1929.
While Barth's response to Brunner can be read in a number of ways, the most helpful is to see it as a rejection of the notion of continuity between the creation and its creator. For Barth, this idea was expressed by the concept of analogia entis: a correspondence between God and the creation resulting from the creation itself. Barth began to focus his attack on the idea of analogia entis from 1929 onward, and it is clear that he saw this notion underlying Brunner's approach to natural theology. Because of Barth's rejection of the analogia entis, human and divine language are not naturally convergent. As Barth later put it in Church Dogmatics, although humans are “permitted and commanded” to speak of God, their language “consists only in ‘approximations' [... and] stands in need of correction at every point.” Even these “approximations” or “pictures” with which humans speak of God are in themselves unsuited to this object and thus inappropriate to express and affirm the knowledge of God. God – the living God who encounters us in Jesus Christ – cannot be appropriated by us in our own capacity. Natural theology thus rests upon a theologically flawed understanding of human nature, with important implications for how we use language about God and construct our concepts of God.
The debate over natural theology has not been settled by this landmark confrontation, and it continues to this day – supplemented by a not unwelcome subsidiary debate over what Barth and Brunner actually thought they were doing in their works of 1934.