In our last post we concluded that juxtaposing Bonhoeffer against himself might not be the most useful way to determine whether the man was a pietistic evangelical or a German liberal. So, how do we sally forth from what some might consider a safe method of departure? Well, let’s begin with Bonhoeffer’s theological and philosophical background and then consider how he appropriated it to his own theology.
Theological and Philosophical Background
In Germany, less than fifty years before Bonhoeffer emerged on the scene, Nietzsche, had made an astute observation. He claimed that God had “bled to death under our knives.” The knives that Nietzsche had in mind were the quills of the philosophers. Through their unbelieving reason he contended that they had murdered God. Surely, Immanuel Kant was one of the more prominent assailants.
After all, when Kant published his book, The Critique of Pure Reason, in 1781 he described it as a Copernican Revolution. Kant’s primary purpose in the Critique was to define the limits and scope of pure reason. In order to accomplish the task he had to answer a crucial question, “What are the necessary conditions of possible experience?” According to Kant, two complimentary conditions need to be met.
First, something must be given to our senses. Kant calls this something a percept or a perception (and at times impressions). Second, a percept must be brought under a mental concept. Or to put it another way, a percept must be brought under the constructive powers of the mind or what Kant calls the transcendental aesthetic and the transcendental analytic. Kant’s pedagogical mode of expression for all of this was that concepts (the empty a priori categories of the mind) without percepts (discrete bits of data tethered to our sense experience) are empty and percepts without concepts are meaningless.
Now, do you see what effectively Kant has done? Follow his logic for a minute. If human beings can know only perceptions which are then constituted by the constructive powers of the mind, then what is the theological implication? God is not a percept that can be processed through the time/space manifold of the transcendental aesthetic so to be understood by the transcendental analytic. Thus, Kant’s conclusion was that human beings cannot know an imperceptible God. If God exists and created, thought Kant, then He created in such a way so as to forbid creation from knowing it.
Now, what does all this have to do with Bonhoeffer? Well, Bonhoeffer recognized this background and accepted it as the Sitz im Leben of the German theological and philosophical landscape. We might even say that Bonhoeffer believed Kant to be asking the right questions—questions worthy of a theologian. In fact, while in America studying at Union Theological Seminary, Bonhoeffer critiqued his American students, saying, “questions such as that of Kantian epistemology are “nonsense,” and no problem to them, because they take life no further” than what is pragmatic. America focused on William James not Immanuel Kant. And Bonhoeffer thought that this was wrongheaded and frustratingly without depth. He wrote that Americans order up theology and philosophy as one ordered a car from the factory!
But what Bonhoeffer did not accept were the conclusions of his colleagues and the theological answers they gave in light of Kantian transcendentalism. For example, Eberhard Bethge, Bonhoeffer’s student and close friend, wrote in his biography that Bonhoeffer “saw Barth establishing the majesty of God by methods of Kantian transcendentalism.” According to Bonhoeffer, Barth had allowed Kant the privilege of asking the questions but problematically he had also allowed Kant the privilege of dictating the answers. For Bonhoeffer, Barth’s response to Kant was to make God remote or wholly other. But, according to Bonhoeffer, Kant had already done that.
For Bonhoeffer, this was unacceptable. The task of the theologian was to bring God near while answering not ignoring men like Kant. Consequently, Bonhoeffer decided to address the situation in his post-doctoral habilitation called, Act and Being: Transcendental Philosophy and Ontology in Systematic Theology. And, not surprisingly, in these opening pages, he writes, “At the heart of the problem is the struggle with the formulation of the question that Kant and idealism have posed for theology.” In this work Bonhoeffer set out to make God immanent rather than transcendent or wholly other. But in order to do that he had to find a way to answer Kantian objections to the knowability of God. How he did that is for our next post.
 Ibid., 158.
 Ibid., 134.