(Here's a theological reflection that diverges from my normal posts on process thought. I've been diving back into post-Barthian theologies this year.)
Every contemporary theologian must somehow respond to Karl Barth’s radically Christocentric critique of natural theology. His famous “No!” to even Emil Brunner’s minimalist form of natural theology simply cannot be pushed aside. However, while the tradition of natural theology has been reevaluated many times over, it has never ultimately died out after Barth. Indeed, the questions that tend to draw out the kinds of reflection that natural theology attempts to respond to have remained – and in some ways increased – for many thoughtful Christians today: What is the place of experience and reason in theology today, especially in the light of liberationist, feminist, black, and queer theologies? How can Christians maintain any common ground with the natural sciences as well as other religions without some form of natural theology? What is the relationship between divine action and history, or divine revelation and biblical criticism?
Because these kinds of questions continue to haunt persons of faith, natural theology has maintained a place of importance for at least some Christians – perhaps especially in Roman Catholic theology, however much its Thomism was chastened by neo-orthodoxy and existentialism. But there were also a number of Protestant theologians who followed in Barth’s wake who attempted to reformulate natural theology in response to his critique. In the United States, one significant theologian to do this was John B. Cobb, Jr. in his Christian Natural Theology. He introduces that text by announcing that he hopes to respond adequately to Barth’s critique of natural theology by realizing Brunner’s attempt to explicate a genuinely Christian natural theology. Cobb aspired to develop a more relativized natural theology that was not based on a naïve assumption of neutral reason and universal experience, but rather on the particular assumptions and experiences of Christians. In Germany, Wolfhart Pannenberg similarly attempted to negotiate a viable natural theology that did not compromise the centrality of the Christian commitment to revelation. For him, natural theology cannot ground faith, although it does serve an important “critical function.” Like Cobb, he attempted to seriously engage the natural and social sciences, history of religions, biblical scholarship, and Western philosophy in order to show a reasonable – although not quite rationalist – approach to Christian faith that avoided what he saw as the irresponsible (and even un-Christian) subjectivism or fideism in Barth’s theological method.
Moltmann then goes on to argue that the “godlessness” of every present stands in total contradiction to God’s promised future: “Hope’s statements of promise…must stand in contradiction to the reality which can at present be experienced…they do not seek to illuminate the reality which exists, but the reality which is coming…present and future, experience and hope, stand in contradiction to each other…” (TH, 3-4). The apparent consequence of this eschatological logic is that natural theology is unable to offer any independent grounds for Christian faith – which is, again, essentially eschatological. Indeed, Moltmann claims that even God must be eschatologically interpreted, with “future as his essential nature” (TH, 2, 15). As such, corresponding to the dialectic of the cross and resurrection of Christ – which stand in absolute contradiction – rationalist natural theology ultimately contradicts rather than corresponds in any way to God’s promises for creation’s future. For Moltmann, the central problem with this kind of natural theology is that it is ultimately idolatrous: it ends in the self-deification of the human knower. The faithful Christian must therefore look first to God’s revelatory promises in history, as narrated in scripture, rather than on reason or experience.
But is this the end of the story for Moltmann? In fact, he does not entirely reject natural theology because he believes that it serves an important function for Christian faith. In his view, revelation can only ever be expressed in “relation to, and critical comparison with, man’s [sic] experience of the world.” The implication is that we cannot simply dismiss the tradition of natural theology, but instead we must properly locate it in relation to revealed theology. Without some kind of natural theology, Moltmann argues that “theology withdraws into a ghetto.” He therefore seeks to show how natural theology can be maintained “between the two extreme possibilities of ghetto and assimilation” (TH, 76). But for Moltmann, natural theology can only ever be expressed “in the light of revelation.” A truly Christian (and therefore eschatological) natural theology will thus not provide foundations or proofs for faith but instead present itself as a series of provisional “anticipations” or “parables” that attempt to faithfully witness to God’s coming future. So even as Moltmann rejects the idea that any form of human reason or experience could ground faith, in the end he does believe that it is necessary to develop some kind of natural theology. As he explains, natural theology must function as “an anticipation of the promised future in history as a result of obedient thinking. Hence it always remains historic, provisional, variable, and open” (TH, 77).
In Moltmann’s later work, this commitment to a revised form of natural theology only deepened – if somewhat ambiguously. In Experiences in Theology, he argues that natural theology is necessary because Christian theology is ultimately a “public theology.” As such, theology must not confine itself “within the closed Christian circle” (ET, 69). He also claims that Barth’s later doctrine of lights is really not so different from the “Christian ‘natural theology’” that he is affirming (ET, 77). But perhaps more than Barth, Moltmann wants to maintain a tension in his method through “a dialectical play of reciprocal knowing – analogia entis in analogia fidei…” (ET, 78). Even as he continues to align with Barth, he believes that Christians living in “multi-faith societies and in a globalized world” must work to “find some common ground where they can present their differences, because otherwise there is no way of presenting them at all” (ET, 82). In his view, the common ground upon which religious and secular truth claims must prove themselves is both “the universe” and “life.” Without a shared commitment to “common life” on our planet, Moltmann worries that humanity and the earth will not survive our escalating 21st century challenges. As I see it, the open question for Moltmann’s post-Barthian method is this: is he able to maintain a dialectical tension between revealed and natural theology, or does he ultimately give up his Barthian commitment to prioritize revelation with this belief in the common ground of life? My Barthian friends think he's gone liberal here, but I'm not so sure - although frankly, I wouldn't think that's such a bad thing.