[1] In the postwar years, Tanabe coined the concept of metanoetics, proposing that the limits of speculative philosophy and reason must be surpassed by metanoia.

[11] The same series published translations of essays by Bruno Bauch, Adolf Reinach, Wilhelm Windelband, Siegfried Marck, Max Planck, Franz Brentano, Paul Natorp, Nicolai Hartmann, Kazimierz Twardowski, Ernst Cassirer, Hermann Cohen, Emil Lask, Victor Brochard, Ernst Troeltsch, Theodor Lipps, Konrad Fiedler, Wincenty Lutosławski, Sergei Rubinstein, Hermann Bonitz, Max Weber, Émile Durkheim, Martin Grabmann, Heinrich Rickert, Alexius Meinong, Karl von Prantl and Wilhelm Dilthey (the series ended before the planned translations of Christoph von Sigwart, Carl Stumpf, Edmund Husserl, Clemens Baeumker, Josiah Royce and Hermann Ebbinghaus were published).

Even more damning are his essays written in defense of Japanese racial and state superiority, exploiting his theory of the Logic of Species to herald and abet the militaristic ideology.

[13] During the war years, however, Tanabe wrote and published little, perhaps reflecting the moral turmoil that he attests to in his monumental post-war work, Philosophy as Metanoetics.

It purports to show a philosophical way to overcome philosophy itself, which suggests[citation needed] that traditional Western thought contained seeds of the ideological framework that led to World War II.

In 1951, he writes: But as the tensions of World War II grew ever more fierce and with it the regulation of thinking, weak-willed as I was, I found myself unable to resist and could not but yield to some degree to the prevalent mood, which is a shame deeper than I can bear.

As James Heisig and others note, Tanabe and other members of the Kyoto School accepted the Western philosophical tradition stemming from the Greeks.

Although the Kyoto School used Western philosophical terminology and rational exploration, they made these items serve the purpose of presenting a unique vision of reality from within their cultural heritage.

Specifically, they could enrich a discussion of the ultimate nature of reality using the experience and thought of various forms of Buddhism like Zen and Pure Land, but embedded in an analysis that calls upon conceptual tools forged and honed in western philosophy by thinkers ranging from Plato to Descartes to Heidegger.

In company with the other members of the Kyoto School, Tanabe believed that the foremost problem facing humans in the modern world is the lack of meaning and its consequent Nihilism.

The Kyoto School philosophers believed that their contribution to this discussion of Nihilism centered on the Buddhist-inspired concept of nothingness, aligned with its correlate Sunyata.

This term differentiates it from the Buddhist religious concept of nothingness, as well as underlines the historical aspects of human existence that they believed Buddhism does not capture.

Tanabe disagreed with Nishida and Nishitani on the meaning of Absolute Nothingness, emphasizing the practical, historical aspect over what he termed the latter's intuitionism.

[18] That is, echoing Kierkegaard's undermining in Philosophical Fragments of systematic philosophy from Plato to Baruch Spinoza to Hegel,[19] Tanabe questions whether there is an aboriginal condition of preexisting awareness that can or must be regained to attain enlightenment.