Immanuel Kant

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Immanuel Kant was a German philosopher, born on 22 April 1724 in Königsberg in East Prussia and dead there on 12 February 1804, having left the city’s hinterland only a handful of times and never the province at all. The biography is famously bare of event: a saddler’s son raised in a Pietist household, educated at the Collegium Fridericianum and the University of Königsberg, employed for years as a private tutor before becoming a Privatdozent and at last, in 1770, professor of logic and metaphysics. The legend of the man whose afternoon walk was so regular that neighbors set their clocks by it is a legend, but it is built on a real temperament — ordered, disciplined, averse to enthusiasm in the eighteenth-century sense of Schwärmerei, the overheated certainty of the inspired visionary. What issued from that quiet life redrew the boundary between what human reason can establish and what lies forever past its reach, and the redrawing is among the few events in the history of philosophy that everything afterward has to step around.

The critical turn

The work that fixed Kant’s place arrived late and fast. After a long stretch of near-silence — the decade between his 1770 inaugural dissertation and the first Critique, in which he published almost nothing — the Critique of Pure Reason appeared in 1781, recast in a heavily revised second edition in 1787; the Critique of Practical Reason followed in 1788, and the Critique of Judgment in 1790. Together the three Critiques — of theoretical reason, of moral reason, and of aesthetic and teleological judgment — carry out what Kant called a Copernican revolution in philosophy. Where earlier thinkers had asked how the mind conforms to objects, he asks how objects must conform to the mind in order to be experienced at all.

The answer is that the mind does not passively receive the world; it actively shapes it. Space and time are not features of things as they are in themselves but forms of intuition, the conditions under which anything can be given to a sensible knower. The categories of the understanding — among them substance and, decisively, causality — are not laws read off the world by observation but the structures through which a manifold of sensation is unified into objects and events at all. Cause and effect, on this account, is not a regularity the mind notices but a condition the mind imposes; this is Kant’s reply to the empiricist doubt, sharpened by David Hume, that causal necessity can ever be found in experience. The world as it appears — the phenomenon — is therefore genuinely structured, lawful, knowable. But the world as it is apart from those conditions, the thing-in-itself, the noumenon, cannot be known. Reason can think it; reason cannot cognize it.

That single move closed off metaphysics in its old confident form and reopened it as a problem. The objects classical metaphysics had claimed to demonstrate — the simple immortal soul, the cosmos as a finished whole, God as a proven being — Kant relocates to the supersensible, the region beyond possible experience, and shows that the proofs traditionally offered for them collapse into contradiction the moment reason tries to extend its categories past the bounds of intuition. The soul, the world-whole, the highest being become not falsehoods but Ideas of reason: regulative, indispensable to the orientation of thought, and forever undemonstrable. Kant’s own formula, in the second edition’s preface, is that he had to deny knowledge in order to make room for faith — the supersensible withdrawn from theoretical reason and reassigned, in the Critique of Practical Reason, to the postulates of the moral will. Freedom, God, and immortality return not as objects known but as the necessary presuppositions of a being under moral law.

Dreams of a Spirit-Seer

Kant’s bearing on the history of esotericism runs along two lines that pull in opposite directions, and the first of them is a single strange book published fifteen years before the first Critique. In 1766, anonymously and at his own expense, he issued Träume eines Geistersehers, erläutert durch Träume der Metaphysik — Dreams of a Spirit-Seer, Illustrated by Dreams of Metaphysics — a sustained, half-mocking examination of Emanuel Swedenborg, the Swedish natural philosopher turned visionary who, from 1745, claimed continuous waking access to heaven, hell, and the world of spirits, and reported seeing events at a distance.

The engagement was not casual. Kant had heard the celebrated anecdotes — the fire in Stockholm that Swedenborg described while three hundred kilometers away in Gothenburg, the lost receipt located through a message from a dead man — and investigated them through Swedish correspondents. His letter of 10 August 1763 to Charlotte von Knobloch treats Swedenborg, whom he had not met, as a reasonable, learned, and open-hearted man, and reports the clairvoyance stories without dismissing them. He paid seven pounds sterling, a serious sum, for the eight quarto volumes of Swedenborg’s Arcana Coelestia — and then, in Träume, called them eight volumes stuffed full of nonsense. The book refuses both to credit the visions and to wave them away, and its genuine target turns out to be double. Having set out the spirit-seer’s reports as unverifiable fantasies built without restraint, Kant turns the same edge on the speculative metaphysicians of the schools, who construct equally confident architectures of the soul and the spirit-world on no firmer ground than the seer’s. The dreamer of sensation and the dreamer of reason are set side by side so that each may discredit the other. The seer builds a spirit-world out of private experience; the dogmatic metaphysician builds one out of pure concepts; neither can show that the thing he describes is so.

The tone is uneasy, and the quarrel over it is old. The mainstream reading takes Träume as a decisive turn against speculative metaphysics — the pre-critical clearing of the ground on which the Critique would later build, the moment Kant learned to distrust any inference that runs past the limits of possible experience, whether the inference wears a mystic’s robe or a professor’s. A revisionist line, running from Ernst Cassirer through Gottlieb Florschütz’s Schwärmerei und Aufklärung (1992), Gregory R. Johnson’s edition and commentary, and Wouter Hanegraaff’s Swedenborg, Oetinger, Kant (2007), reads the irony as a mask: on this account Swedenborg’s metaphysics of two simultaneously inhabited worlds — a natural order and a spiritual order corresponding to it — left a real mark on the distinction between the phenomenal and the noumenal that organizes the critical philosophy. Hanegraaff’s larger point is that Swedenborg’s German and Kantian readers fastened on the spectacle of spirit-seeing and ignored the painstaking biblical exegesis that Swedenborg himself thought was the whole of his work. Scholars still divide over how much of Träume is ridicule and how much is suspended judgment honestly held, and the book is read on both sides for what it withholds as much as for what it says.

The frontier and its two readings

The second line is structural, and larger than any single book. By holding that the supersensible cannot be an object of knowledge, Kant fixed the terms within which everything that came after — including the esoteric currents that the nineteenth century would produce — had to operate. He did not so much answer the old questions about the soul and the unseen world as relocate them, and the relocation left a frontier that could be read in two incompatible ways. Both readings cite exactly the same pages.

One reads Kant as an unlikely ally. If theoretical reason cannot reach the thing-in-itself, then natural science, however far it advances, can never close the door on a deeper reality; the supersensible is barred to argument, but it is not thereby shown not to exist. Into the space that Kant had cleared and then declared off-limits, a different faculty might enter — intuition, contemplation, a trained inner perception that begins precisely where conceptual knowledge ends. This is the appeal made by Theosophy in the wake of Helena Blavatsky and, with more philosophical care, by Rudolf Steiner. Steiner’s early work is an objective-idealist revision of Kant’s theory of cognition: he argues that intuitive thinking lies at the very heart of ordinary experience, and that if this is so, then a disciplined supersensible cognition must be possible in principle — a knowing of the higher worlds developed by exercise. The current he founded, Anthroposophy, takes its bearings from exactly this claim: that there is an exact investigation of the supersensible, beginning where Kant said knowledge stopped, his title for the introductory statement of the program announcing a knowledge of the supersensible world. The Kantian limit, on this reading, is not a wall but a threshold — a door left unbolted.

The other reading takes Kant as the great closer of doors: the thinker who made sober philosophy permanently inhospitable to the occult by showing that every claim to know the unseen, the seer’s and the system-builder’s alike, overreaches the only kind of knowing human beings possess. On this account the Critique finished what Träume began. The supersensible is not a country temporarily beyond the map; it is the region the map by its nature cannot cover, and the honest response is silence rather than a new organ of perception. Steiner’s whole effort can be described, accurately, as an attempt to transcend the limit Kant had placed on human knowledge — and whether that attempt succeeds or simply denies the limit is the very point in dispute. The two receptions agree on the geography and disagree on what it permits.

Kant within and against the older speculative tradition

The decentered placement of Kant against the speculative theology he displaced is clarifying. Three centuries before the Critique, Nicholas of Cusa had argued, in De Docta Ignorantia (1440), that the highest reach of the mind is the reasoned recognition that the infinite exceeds all finite comparison — finiti et infiniti nulla proportio, between the finite and the infinite there is no proportion. That doctrine of learned ignorance is, on its surface, a recognition of a limit not unlike Kant’s: a boundary past which the discursive intellect cannot pass. But the two limits are differently sloped. Cusanus’s ignorance is learned — it opens onto the coincidentia oppositorum, the contemplative apprehension of a unity in which opposites coincide, and the not-knowing is itself a mode of touching the infinite. Kant’s limit is critical: it forecloses the speculative ascent that the Neoplatonic inheritance, from which Cusanus drew, had always promised. Where the older apophatic tradition treats the dark beyond the concept as a presence to be entered, Kant treats it as a region about which theoretical reason can establish nothing whatever. The esoteric readers who later enlisted him were, in effect, trying to restore the Cusan slope — to make the limit a threshold again.

Within his own century Kant stands at the far end of a long argument he resolves rather than joins. The continental rationalism of René Descartes had grounded knowledge in the self-certainty of the thinking subject and built outward to God and the world by inference; the empiricist line traced knowledge back to sensation. Kant’s critical philosophy is sometimes described as the synthesis that dissolves the quarrel: experience without the mind’s organizing forms is blind, and the forms without sensible content are empty, so neither pure reason nor pure sense is the source of knowledge — knowledge is their joint work, strictly bounded by the reach of possible experience. The empiricist John Locke, whose mind began as a blank surface written on by sensation, and Pierre Gassendi, who revived the atomism of Epicurus against the schoolmen, are figures Kant incorporates only by transforming: he keeps the empiricist insistence that knowledge requires sensible content and rejects the empiricist claim that sensation alone explains its lawful form. The supersensible questions that the older metaphysics had argued over he does not settle — he removes them from the court that claimed jurisdiction.

Scholarship and the texts

The modern recovery of the man behind the system rests on Manfred Kuehn’s Kant: A Biography (Cambridge University Press, 2001), the first full-length life in more than fifty years, which dismantles the caricature of a pure thinker with no life of his own and reconstructs the Enlightenment Königsberg — its commerce, its sociability, its Pietism — in which the critical project took shape. Kuehn’s account is a watershed-not-partisan one: it neither enlists Kant for any esoteric program nor flattens the Träume episode into mere mockery, and it (Cambridge University Press) anchors the reading of Kant’s temperament — the order, the punctuality, the deep distrust of Schwärmerei — in documented life rather than legend.

For the esoteric reception, the indispensable apparatus is the revisionist Swedenborg–Kant scholarship: Gregory R. Johnson’s Kant on Swedenborg: Dreams of a Spirit-Seer and Other Writings (Swedenborg Foundation, 2002), which gathers the relevant texts in English with commentary, and Wouter Hanegraaff’s Swedenborg, Oetinger, Kant: Three Perspectives on the Secrets of Heaven (Swedenborg Foundation, 2007), the major short comparative study locating Kant within the disciplinary history of Western esotericism. The primary text itself is in the public domain: the German Träume eines Geistersehers is freely available through Project Gutenberg, and the Goerwitz English translation of 1900 circulates under the title Dreams of a Spirit-Seer. Against these the mainstream Kant literature — the standard reading of Träume as the pre-critical turn against dogmatic metaphysics, and of the Critiques as the closing of the supersensible to theoretical reason — sets the counterweight, so that the two interpretive traditions can be read against the same documents.

The line both receptions argue over is, in the end, the thing-in-itself: the object as it is apart from every condition under which a mind could meet it. Kant named it precisely in order to mark it as unreachable — the limit-concept at the edge of cognition, indispensable to thought and closed to knowledge. The Theosophist reads that frontier as an invitation, the place where a higher organ of perception is to begin; the sober heir reads it as the edge of the speakable, past which the discipline of the Critique requires the philosopher to stop. Neither dissolves the line that divides them, because the line is Kant’s own and holds whichever way it is read: by positing the thing-in-itself he granted the unseen its full reality and in the same stroke placed it past the reach of every faculty that could be called knowing. The man who walked each afternoon to the edge of his town and turned back had drawn, in thought, the boundary he kept in his feet — and he meant the turning back.

→ Related: Theosophy · Learned Ignorance Docta Ignorantia · Emmanuel Swedenborg · Theosophy Anthroposophy · Rudolf Steiner · Reason · Metaphysics · Empiricism · Noumenon · John Locke · Pierre Gassendi · Rene Descartes · Nicholas Of Cusa · Neoplatonism