Kant and his writings have been seen variously as champions of theism and as destroyers of faith. Was the net impact of his texts to solidify belief in God as a solidly rational viewpoint, or to undermine any rational foundation for theism?
Norbert Hinske documents both hypotheses. Hinske identifies Moses Mendelssohn as an originator of the view that Kant’s Critique of Pure Reason poses a threat to theism:
Für Mendelssohn, der aufgrund seiner Krankheit Kants Werk freilich nur vom Hörensagen kennt - „aus unzulänglichen Berichten meiner Freunde oder aus gelehrten Anzeigen, die selten viel belehrender sind“ -, ist die Kritik also ein Werk, das alle „vernünfitgie Erkenntniß Gottes“ zu zerstören droht.
Mendelssohn’s view was amplified and transmitted through the writings of Ludwig Ernst Borowski:
Mendelssohns Rede vom „alles zermalmenden Kant“ hat Karriere gemacht. Schon Borowski erwähnt sie 1804 in seiner immer wieder nachgedruckten Kantbiographie. Zum Substantiv verschärft, ist das Wort vom Alleszermalmer dann zu einer der geläfigsten Charakterisierungen Kants avanciert.
This view of Kant seeped from the world of academic philosophy to a broader audience through, e.g., the writings of Heinrich Heine, who echoed the words of Mendelssohn and Borowski, and saw Kant as a destroyer of faith and hope.
On the other hand, Hinske describes the early Kantians at the University of Jena, who saw Kant as the defender of theism. In the Kritik, Kant finds arguments for and against the existence of God to be futile, because reason is based on, or arises from, the forms of perception. God is not a perception, i.e., not a phenomenon, but rather a thing-in-itself: a Ding-an-sich. As a noumenon, God is not subject to the type of reasoning which is based on the forms of phenomena.
The early Kantians at Jena, philosophers and theologians, saw Kant as constructing a defense of theism against any allegedly rational arguments for atheism. If one accepts Kant as he expresses himself in the first Kritik and other writings, then one cannot countenance arguments against the existence of God.
Two centuries later, Kant remains a mixed picture. Perhaps the reason for conflicting readings of the Kritik is that, on the one hand, Kant removes the possibility of rational argumentation from both sides: he will accept no line of reasoning which hopes to establish either atheism or theism. He places the existence of God as a question which is beyond pure reason. It is such points in Kantian thought which later give a starting point to Schopenhauer and postmodernism in the sense of post-rationalism.
On the other hand, Kant famously points to the existence of God as a necessary hypothesis in the second Kritik. But Kant finds his way to God in the Kritik der Praktischen Vernunft in a manner that disappoints both theists and atheists. The atheists are unhappy that Kant has pointed to the necessity of God’s existence, but the theists are also unhappy, because Kant doesn’t leave room to prove that God has the robust collection of metaphysical characteristics of traditional theism.
