is distinct from that of philosophy. An examination of the history of philosophy shows its fundamental dialectic to be concerned with a constant tension between realism and idealism. But that is also the dialectic in which theology engages in its movement between the given object and thought about the object, and therefore it must be in this dialectic that the relevance of philosophical thinking for theology is to be found.
In the first place, then, theology must face the critical questions posed by philosophy as to objectivity, givenness, or reality—that is the problem of realism. Classical realism holds that all our knowledge arises out of actual experience of a given reality, but it also admits that this involves an outward and an inward experience, an objective and a subjective givenness. How, then, are we to distinguish the independent objective reality from our experience of it, especially from our inward subjective experience of it? That is the question that a realist theology must face. It takes as its fundamental proposition that God is, and so affirms that God has reality independently of our knowledge of him. As Anselm expressed it, it is one thing to say that something exists in the understanding, and another thing to understand that it exists. But how in point of fact are we to distinguish the two? How do we know that the God whom we know in our minds has existence apart from our mental knowledge of him, that ‘God’ is anything more than an empty ‘idea’ in our minds?
That problem is made all the more acute when we remember that the God we claim to know is not some God in himself, but God who is known in his Word, the God who reveals himself within the concrete objectivities and actualities of our human and historical existence; that is, within the Church of Jesus Christ on earth. How are we to distinguish God from the outward experience of these concrete objectivities in the I-Thou encounter we have with other people, or in the concrete objectivities of history? Theological realism insists that God is given to me in the actualities of my experience in the form of a likeness to himself, in the realm of being which I have in nature and history, and that he meets me in my neighbour and within the subject-subject encounter of person to person in the Christian Church. But how am I to distinguish God himself from these external objectivities through which he reveals himself to me? And if I hold that God is the source of all Being, and that all other being derives from him and participates in him, and if therefore I think that in virtue of the fact that I exist or have being I am necessarily in encounter with the Being of God, how can I distinguish him from the actualities with which my existence is necessarily bound up? How can I distinguish God from necessity or from fate or from nature, or from the concrete historical existence which I share and from which I cannot escape? How can I distinguish a genuine theological realism from a philosophical realism, or reflection about the living God from reflection upon being in general?
These questions are sufficient to show that realism is a very serious issue for theology, but theology has its counter-questions to ask, says Barth. The most fundamental of them is whether theological realism takes into consideration the fact that the grace of God contradicts us. It is on this ground, that grace opposes sinful man, and objects to his sin, on the ground of a contradiction between the revelation of God and the activity of man, that we can distinguish the objectively given reality of God-in-his-Word from our own subjective states, but also from the other objectivities we encounter in our experience of the world around us. Classical theological realism operates with a basic, naïve conviction that we are able to read knowledge of God off what is given to us in our experience because we stand in relation to him by virtue of the fact that we exist. But when we actually know God through his Word a very different conviction arises, for here a light shines into our darkness, and something quite new is revealed to us which does not just reinforce what we already know, but rather calls it in question. This new knowledge comes as grace that forgives and judges us, and which we cannot just assimilate into our existence, for it lays claim upon us and summons us to encounter the independent objective reality of the living God, the Creator and Redeemer.
Concretely this is what happens when we meet God in Jesus Christ and know him as Lord by the power of the Spirit. It is in that encounter that we learn that the objective act of God upon us in the freedom of his Spirit is to be distinguished from our inward subjective conditions, and that the God who meets us face to face in Jesus Christ is not just nature, or history, or the actuality of our existence with which we are bound up and from which we cannot escape, but a living God who really comes to us and acts upon us in the midst of all the other actualities and objectivities of our historical and natural existence. In other words, here we are faced with a deeper and more fundamental objectivity, with the ultimate objectivity of the Lord God, and therefore it is here that theology is both basically realist and yet to be distinguished from every form of philosophical realism.
In the second place, however, theology must face the critical question posed by philosophy as to the adequacy of its thought to its proper object—that is the question of truth, which gives rise to the problem of idealism. This is the question that seeks to penetrate behind the given, the finite, the objectifiable, and behind all actuality to its ultimate validation or presupposition. Idealist thinking, says Barth, has a negative critical side, and a positive speculative side. On the one hand, it questions the basic assumption of realism, inquires into the reliability of the correlation between subject and object, and reveals the limits within which realist thinking can operate. It refracts or breaks the movement of realist thinking, and so makes it point beyond itself to its object. This critical operation both reminds us of the inadequacy of our human thought-forms and calls for a greater and more exacting adequacy. But idealist thinking has another speculative side, in which it poses as the criterion of reality and exalts itself over against pure being. Idealism of this sort is the self-reflection of man’s spirit over against nature, the discovery of the creative reason as the source of the correlation between subject and object.
Idealist thinking, at least in its critical form, is a necessary element in theological thinking, for whenever there is serious thinking about God, a distinction must be drawn between the givenness of God and the givenness of all other being. That is the relevance of mysticism or of the via negativa even for the classical realism of the Middle Ages, for a realist theology requires a powerful element of idealism in order to be genuinely realist. Is the idealist distinction between ‘the given’ and ‘the not-given’ not necessary for a proper understanding of the difference between divine revelation and all other knowledge that claims to be knowledge of God? And just because in theology we are engaged in human thinking about God, and with the articulation of knowledge of God in human thought-forms, must we not ask the question as to the adequacy of these thought-forms to God? Does not idealist thinking teach us that the best of our thought-forms can only point beyond to the ultimate reality of God which cannot be captured and formulated within the four corners of our human concepts and propositions? That is why idealism is the necessary antidote to all thorough-going realism, for it prevents realist thinking from confounding God with the actualities of our existence, with nature, or history, or necessity.
But may not idealism itself prove the greater danger, especially when it refuses to rest content with the humble critical refraction of our thinking, but insists on making out of the reason itself the criterion of truth, and so exalting itself above God? Is not the danger of idealist thinking in theology that it may lead to the substitution of ideology for genuine theology, a system of self-sufficient truth for an activity of human thinking that points away from itself to the object of its knowledge as the sole source and ground of truth, and as the Truth of God? Hence here, too, theology has its counter-questions to ask of idealist thinking in theology.
The fundamental question we have to ask is directed to the idealist question posed not from the side of the object but from the side of the subject. Does the attempt to reach out beyond all the dialectical antitheses and antinomies of human thought to an ultimate synthesis ever really get outside the circle of its own subjectivity, ever really get beyond the human subject from which it started? Does it not, after all, confound God with the conclusion to its own argument or with the goal of its own upward movement of thought? Is it not in the end projecting its own thought into the infinite and calling it God?
The fundamental question theology must put to the idealist is whether
