WorkImmanuel Kant

Prolegomena to Any Future Metaphysics

Kant's 1783 rescue of his own unreadable masterpiece: the Critique of Pure Reason rewritten short and backwards, and still the standard way in.

by Immanuel Kant434 passages held

German, the original language
English, a translation held here, and your language

First published: 1783(aged 59)
Original language: German

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Overview

The great book had failed to land. Kant had spent a decade on the Critique of Pure Reason, published it in 1781, and watched it meet silence and then a review that got it exactly backwards. So in 1783 he did what a proud author rarely does: he wrote the thing again, shorter, from the other end. Where the Critique had built its case brick by brick, the Prolegomena starts from a fact nobody disputed — that mathematics and mathematical physics do give us certain knowledge that outruns experience — and works backwards to ask what our minds must be like for that to be possible. The same doctrine arrives, cleaner: that we can know the world only as it appears under the forms our own sensibility and understanding impose, and that metaphysics as it had been practised, reaching past all possible experience, cannot be a science. The book carries a scar. Its appendix is a controlled fury aimed at the Göttingen review that had called Kant a Berkeleyan denying the existence of matter, and much of the Prolegomena's sharpness about what his idealism is and is not was forced out of him by that misreading. It did the job the Critique could not: generations of readers have entered Kant through this book first, and it remains the standard doorway into the hardest philosophy of the modern age.

Key concepts

What is the 'analytic,' or regressive, method of this book?

Rather than building forward from first principles as the Critique did, the Prolegomena starts from a fact nobody disputes — that mathematics and mathematical physics do give certain knowledge reaching beyond experience — and reasons backward to the conditions that must hold for it to be possible. It is the very same argument run in reverse, from result to ground.

What is the 'synthetic a priori' question the whole book turns on?

How can we have judgments that are at once necessary and universal (a priori) and genuinely informative rather than merely definitional (synthetic) — the truths of mathematics, or 'every event has a cause'? That such knowledge exists is granted from the start; explaining how it is possible is the task, and this is the guiding question every section returns to.

What are the three questions the Prolegomena is organized around?

How is pure mathematics possible? How is pure natural science possible? And how is metaphysics possible at all? Kant answers the first two to expose what is wrong with the third: as it had been practised, metaphysics reached past all possible experience, where no science can follow, so it cannot yet be a science in the way the other two are.

Why did Kant write the Prolegomena at all?

Because the Critique had failed to land — a decade of work met with silence and then a Goettingen review that called it warmed-over Berkeley, an idealism denying the real world. Stung, Kant rewrote the argument short and backwards to be understood, and appended a controlled fury against that misreading. The result became most readers' first door into his philosophy.

Themes of the book

What this book returns to, gathered into themes and ordered by how much of the text each one occupies.

The Standard Way In

Mathematics plainly gives us certain knowledge that outruns experience — so what must our minds be like for that to be possible, and how far does the same power reach?

Written to rescue the Critique of Pure Reason from its baffled reception, the book runs the same argument in reverse: it starts from a fact nobody disputed, that mathematics and mathematical physics yield certain knowledge beyond experience, and works backward to the conditions that make it possible. The doctrine arrives cleaner — that we can know the world only as it appears under the forms our sensibility and understanding impose, so metaphysics reaching past all experience cannot be a science. An appendix answers, with controlled fury, the review that had called Kant a Berkeleyan denying matter; the book became most readers' first door into him.

metaphysics
epistemology
limits of knowledge
reason
methodology
certainty
mathematics
knowledge
dogmatism
skepticism
experience

Enter a dialogue

Within this work

passages held: 434
distinct concepts: 310
by passages held, corpus-wide: #171

What this book thinks together

The wheel takes this book’s leading concepts and shows how often they come up together. The wider the band between two, the more of its passages speak of both. Among them, most often together: “a priori knowledge” and “metaphysics”.

Concept co-occurrence, strongest first 8 concepts, joined by 26 pairings. 82 pairings reach beyond these concepts and are not drawn.
Concept	Paired concept	Shared passages
a priori knowledge	metaphysics	34
a priori knowledge	experience	28
metaphysics	reason	25
experience	understanding	21
experience	metaphysics	16
categories	experience	15
causality	experience	15
a priori knowledge	causality	13
experience	transcendental idealism	12
a priori knowledge	transcendental idealism	11
experience	reason	11
a priori knowledge	understanding	8
categories	metaphysics	8
a priori knowledge	reason	6
reason	understanding	6
transcendental idealism	understanding	6
a priori knowledge	categories	5
metaphysics	understanding	5
causality	metaphysics	4
categories	causality	3
categories	understanding	3
causality	reason	3
categories	reason	1
categories	transcendental idealism	1
causality	transcendental idealism	1
metaphysics	transcendental idealism	1

Works held

The author's work in order, this book marked in place. Your-language title first, the original beneath it where the two differ; side chips show which full texts are held.

1764 Inquiry Concerning the Distinctness of the Principles of Natural Theology and Morality (Untersuchung über die Deutlichkeit der Grundsätze der natürlichen Theologie und der Moral)
Kant's runner-up entry in the Berlin Academy's prize contest, and the sharpest of the pre-critical essays: it already sets philosophy's method against mathematics', the problem the first Critique would finally resolve.
DE
1764 Observations on the Feeling of the Beautiful and Sublime (Beobachtungen über das Gefühl des Schönen und Erhabenen)
The popular essay of Kant's pre-critical years, twenty-six years before the Critique of Judgement gave taste a rigorous grounding; its remarks on race and sex now drive much of the scholarship on him.
DE
1766 Dreams of a Spirit-Seer, Elucidated by Dreams of Metaphysics (Träume eines Geistersehers, erläutert durch Träume der Metaphysik)
The anonymous, ironic book of 1766 in which Kant's faith in speculative metaphysics visibly collapses — the clearing of the ground that the first Critique, fifteen years later, would build on.
DE
1781 The Critique of Pure Reason (Kritik der reinen Vernunft)
The book at the centre of everything after it: the first of the three Critiques, revised almost past recognition for its 1787 second edition, and the work the Prolegomena was written to explain.
DEEN
1783 Prolegomena to Any Future Metaphysics you are here DEEN
1784 An Answer to the Question: What Is Enlightenment? (Beantwortung der Frage: Was ist Aufklärung?)
The most quoted thing Kant wrote, and among the shortest: a 1784 magazine answer to a question a Berlin pastor had left hanging, and the defining slogan of the German Enlightenment.
DE
1784 Idea for a Universal History with a Cosmopolitan Purpose (Idee zu einer allgemeinen Geschichte in weltbürgerlicher Absicht)
The essay where Kant first treats history as more than chronicle — nine propositions arguing it has a hidden rational shape; the seed of Perpetual Peace, and a device Hegel later took over.
DE
1785 Fundamental Principles of the Metaphysic of Morals (Grundlegung zur Metaphysik der Sitten)
The short, deliberately preliminary book that isolates the categorical imperative before building anything on it; three years later the Critique of Practical Reason would give the same moral law its fuller grounding.
DEEN
1786 What Does It Mean to Orient Oneself in Thinking? (Was heißt: sich im Denken orientieren?)
An intervention in the pantheism controversy that split the German Enlightenment: written months after Mendelssohn's death, it stakes out a rational faith between dogmatic proof and Jacobi's leap.
DE
1788 The Critique of Practical Reason (Kritik der praktischen Vernunft)
The second of the three Critiques, and Kant's reply to those who doubted the Groundwork's freedom; it introduces the fact of reason and the postulates of God and immortality.
DEEN
1790 Critique of Judgement
The book the Romantics and the German Idealists built on: Kant's 1790 account of beauty and of purpose in nature, written to bridge the gulf that had opened between his first two Critiques.
DEEN
1793 Religion within the Boundaries of Mere Reason (Die Religion innerhalb der Grenzen der bloßen Vernunft)
The book that got Kant ordered to stop writing on religion: four essays, from 1793, rebuilding Christian doctrine on reason and consigning revelation and clergy to what Kant called counterfeit service.
DE
1795 Perpetual Peace: A Philosophical Sketch (Zum ewigen Frieden: Ein philosophischer Entwurf)
The late essay whose plan for a league of free states reached the twentieth century intact; Kant, past seventy, wrote it as Prussia pulled out of the war against revolutionary France.
DE
1797 Introduction to the Doctrine of Right (Einleitung in die Rechtslehre)
The framing section of the Doctrine of Right, the legal half of Kant's 1797 Metaphysics of Morals; it defines a right through freedom alone and ties every right to a power to coerce.
DE
1797 The Metaphysical Elements of Ethics (Die Metaphysik der Sitten)
Long read as a mere appendix to the Groundwork, this ethical half of the 1797 Metaphysics of Morals is where Kant spells out the duties of virtue; later Kantians recovered it as his theory of character.
DEEN
1798 On the Power of the Mind to Master Its Morbid Feelings by Sheer Resolution (Von der Macht des Gemüts, durch den bloßen Vorsatz seiner krankhaften Gefühle Meister zu sein)
The third part of Kant's late Conflict of the Faculties (1798), written as a reply to the physician Hufeland — a philosopher's dietetics, and his most personal page on governing the body through the mind.
DE
1803 Lectures on Pedagogy (Über Pädagogik)
One of the last books to appear under Kant's name (1803), though his editor Rink built it from lecture notes; the fullest record of Kant on education, and of his debt to Rousseau.
DE

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