Kant's Problem of Certainty in Anthroposophy

Updated: August 2026
Glossary Anthroposophy 4 min read
Kant's Problem of Certainty n.

Steiner's name for the real driver of Kant's philosophy: not truth, not knowledge, but the demand for judgments certain forever, purchased at the cost of knowledge itself.

Kant's Problem of Certainty in Anthroposophy is Rudolf Steiner's diagnosis, delivered in the Philosophy lecture of 4 April 1921 at Dornach (GA 76, The Stimulating Effect of Anthroposophy on the Individual Sciences), that Kant's critical philosophy was never a search for truth or for knowledge but a search for certainty. Trained in the Wolffian school yet shaken by Hume, Kant wanted judgments valid forever, and he rescued them by letting human reason impose its own forms upon experience. Steiner's verdict: this move quietly dethrones knowledge itself, since the world we know becomes partly our own manufacture. The bearer of the problem is the human intellectual soul, which in the consciousness-soul age must win certainty through strengthened thinking rather than surrender it. Steiner answers Kant in Truth and Science (1892) and The Philosophy of Freedom (1894); readers today meet the same question in John Dewey's The Quest for Certainty (1929).

Kant's Problem of Certainty names the hidden engine of the Critique of Pure Reason as Steiner read it: a compulsion to secure judgments that hold forever. To keep them safe from the flux of experience, Kant made reason the lawgiver of nature, and paid for the rescue with knowledge of reality itself. Steiner treats this bargain as the decisive wrong turn of modern philosophy, and his own epistemology as its correction.

Kant's problem is not a problem of truth, nor of knowledge, but of certainty. And if you don't grasp it as a problem of certainty, you can't really understand it. Kant seeks the solution by saying: the human soul is certainly not suited to distilling judgments of reality out of reason, but these judgments do come about; they are applied to external experience, as can be seen, for example, in mathematics. We do not merely look at such figures (it is drawn), but we look at them mathematically and say: there are two triangles or, drawn differently, it is a hexagon. We mix what we spin out of reason inwardly with what comes to us through external experience. We impose what we recognize inwardly a priori over what we experience a posteriori.

Rudolf Steiner, The Stimulating Effect of Anthroposophy on the Individual Sciences (GA 76, lecture of 4 April 1921, Dornach)

Eight years after this Dornach lecture, John Dewey delivered the 1929 Gifford Lectures in Edinburgh, published the same year as The Quest for Certainty. Dewey's argument runs on a track strikingly close to Steiner's: Western philosophy, he held, was driven less by love of wisdom than by a craving for security, a wish to escape the risks of action into a realm of fixed and finished being. Kant serves both thinkers as the great case study, the philosopher who saved certainty by moving its guarantee inside the mind. The two physicians, however, prescribe opposite cures. Dewey dissolves the craving: abandon the demand for certainty and let knowledge become experimental inquiry, tested by consequences. Steiner refuses to lower the goal. In Truth and Science (1892) and The Philosophy of Freedom (1894) he argues that thinking, observed in the act and strengthened by discipline, is no subjective stamping machine but a real participation in the lawfulness of the world.

Thalira synthesis: Kant mistook a developmental stage of consciousness for a permanent boundary, so where Dewey cures the craving for certainty by shrinking the claim of knowledge, Steiner cures it by growing the knower. The practice implication is concrete. Observe your own thinking while it works, as The Philosophy of Freedom directs, and the certainty Kant despaired of finding within experience appears as the one thing experience cannot dissolve.

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