Immanuel Kant

1724 — 1804

royaume de Prusse

PhilosophyPhilosopheEarly Modern18th century (Enlightenment – German Aufklärung)

German Enlightenment philosopher (1724–1804), Kant revolutionized metaphysics by proposing a radical critique of human reason. Author of the Critique of Pure Reason, he founded transcendental idealism and developed a universal moral theory based on the categorical imperative.

Émotions disponibles (6)

Neutre

par défaut

Inspiré

Pensif

Surpris

Triste

Fier

Famous Quotes

« Sapere aude! (Dare to know!) »

« Act only according to that maxim by which you can at the same time will that it should become a universal law »

« Two things fill the mind with ever new and increasing admiration and awe, the more often and steadily we reflect upon them: the starry heavens above me and the moral law within me »

Key Facts

1781 – Publication of the Critique of Pure Reason, a foundational text of modern philosophy
1785 – Publication of the Groundwork of the Metaphysics of Morals, presenting the categorical imperative
1788 – Publication of the Critique of Practical Reason, developing his moral philosophy
1790 – Publication of the Critique of the Power of Judgment, reconciling theory and practice
1804 – Death in Königsberg, the city he never left throughout his entire life

Works & Achievements

Critique of Pure Reason (1781 (2nd ed. 1787))

Founding work of critical philosophy, it examines the conditions and limits of human knowledge, distinguishing between phenomena and noumena.

What Is Enlightenment? (1784)

Short essay that became emblematic of the Enlightenment movement, defining it as the emancipation of the individual through the autonomous use of reason.

Groundwork of the Metaphysics of Morals (1785)

Work in which Kant formulates the categorical imperative, the foundational principle of his universal moral philosophy.

Critique of Practical Reason (1788)

The Second Critique, devoted to morality, in which Kant establishes that the moral law imposes itself on reason as an undeniable fact.

Critique of the Power of Judgment (1790)

The Third Critique, concerned with aesthetic judgment and teleological judgment, bridging the gap between nature and freedom.

Perpetual Peace: A Philosophical Sketch (1795)

Visionary political essay proposing a federation of free states and principles of international law, considered a precursor to the idea of a League of Nations.

Universal Natural History and Theory of the Heavens (1755)

Work on cosmology in which Kant proposes a theory of the formation of the solar system from a primordial nebula, anticipating the work of Laplace.

Anecdotes

Kant was so legendarily punctual that the inhabitants of Königsberg set their watches by the time of his daily walk. Every afternoon, at exactly 3:30 PM, he would cover the same route along the Linden Alley. The only time he missed his walk was the day he received Rousseau's Émile, so captivated was he by his reading.

Kant never left the Königsberg region his entire life, never straying more than a few dozen kilometers from his hometown. Yet, through his reading and the accounts of travelers, he gave lectures on physical geography so detailed that his students believed him to be a seasoned traveler.

For years, Kant invited guests to lunch at his home every day, as he detested eating alone. These meals often lasted several hours and were animated by conversations covering every subject except philosophy. Kant believed the dining table should be a place of pleasure and lightness.

Kant came from a modest family of saddlers of Scottish origin. His mother, Anna Regina, a devout Pietist, took him from a very young age to observe the stars and instilled in him a deep moral sensibility. Kant always spoke of his mother with great tenderness, claiming she had planted in him the first seed of goodness.

Primary Sources

Critique of Pure Reason (Kritik der reinen Vernunft) (1781)

Thoughts without content are empty, intuitions without concepts are blind. It is therefore just as necessary to make concepts sensible as it is to make intuitions intelligible.

What is Enlightenment? (Was ist Aufklärung?) (1784)

Enlightenment is man's emergence from his self-imposed immaturity. Immaturity is the inability to use one's understanding without guidance from another. Sapere aude! Have the courage to use your own understanding!

Groundwork of the Metaphysics of Morals (Grundlegung zur Metaphysik der Sitten) (1785)

Act only according to that maxim whereby you can at the same time will that it should become a universal law.

Critique of Practical Reason (Kritik der praktischen Vernunft) (1788)

Two things fill the heart with ever new and increasing admiration and awe: the starry heavens above me and the moral law within me.

Key Places

Königsberg (now Kaliningrad)

Kant's birthplace, where he spent his entire life. He taught at the university there for more than forty years and composed the entirety of his work.

Albertina University of Königsberg

Founded in 1544, this university was the setting for Kant's entire academic career, first as a student and then as a full professor of philosophy.

Königsberg Cathedral

Kant was interred in the professors' portico adjoining the cathedral. His tomb, rebuilt in 1924, is today a visited memorial site.

Philosophers' Walk (Philosophengang)

A shaded promenade along the Pregel River that Kant walked every afternoon with a punctuality that became proverbial.

Kant's House, Prinzessinstraße

Kant's last residence in Königsberg, where he lived from 1783 and where he received guests daily for lunch.

Typical Objects

Quill pen and inkwell

Kant's daily writing instruments, with which he wrote his entire critical body of work in his study in Königsberg.

Nightcap

Kant wore a nightcap following a very precise bedtime ritual. He would methodically wrap himself in his blankets using a technique he had devised himself.

Pocket watch

An indispensable object for Kant, who organised every minute of his day with a mechanical regularity that became legendary.

Walking cane

Kant carried his cane on his daily walk along the Philosophers' Alley in Königsberg, an unchanging ritual maintained for decades.

Telescope

Kant had an interest in astronomy and cosmology. He formulated a theory on the formation of the solar system, known as the Kant-Laplace hypothesis.

Snuff box

Kant regularly took snuff. His snuff box was one of the few personal objects he was attached to, kept permanently on his desk.

School Curriculum

LycéePhilosophie

LycéePhilosophie — Les limites et possibilités de la connaissance humaine

LycéePhilosophie — La morale : le devoir et l'impératif catégorique

LycéePhilosophie — La liberté comme fondement de la moralité

LycéePhilosophie — Le rapport entre la raison théorique et la raison pratique

LycéePhilosophie — L'autonomie de la volonté et l'universalité morale

LycéePhilosophie — La critique de la métaphysique dogmatique

LycéePhilosophie — Les conditions a priori de l'expérience

Vocabulary & Tags

Key Vocabulary

Categorical imperative: universal moral principle requiring us to act only according to maxims that could be universalizedTranscendental idealism: doctrine holding that space and time are a priori forms of our sensibilityPhenomenon: a thing as it appears to us after being structured by our mindNoumenon: the thing-in-itself, unknowable by human reasonA priori: knowledge independent of experienceSynthetic a priori: a judgment that adds new information while remaining necessary and universalAutonomy: the capacity of a rational being to give itself its own moral lawAufklärung: the German Enlightenment movement, of which Kant is a central figure

Daily Life

Morning

Kant rose every morning at exactly 5 o'clock, woken by his manservant Lampe. He would drink one or two bowls of weak tea while smoking a pipe, then work on his writings and prepare his lectures in his study until it was time for his university classes.

Afternoon

Kant gave his lectures in the morning, then received guests for a long and lively lunch, his only real meal of the day. At precisely 3:30 p.m., he set out for his daily walk along the Philosophers' Walk, always alone so that he could breathe through his nose and meditate in silence.

Evening

In the evenings, Kant read works on natural science, geography, or literature. He went to bed at exactly 10 p.m., wrapping himself in his blankets according to a meticulous ritual he had devised himself to fall asleep quickly.

Food

Kant ate only one main meal a day — lunch — consisting of several simple but hearty courses: meat, fish, vegetables, and cheese, accompanied by wine and followed by mustard, of which he was particularly fond. He avoided eating supper in the evening, sometimes making do with a little tea.

Clothing

Kant dressed with sober, careful elegance, typical of an 18th-century Prussian professor: a dark cloth coat, waistcoat, knee breeches, white stockings, and buckled shoes. He wore a powdered wig in his youth, before abandoning it toward the end of the century.

Housing

Kant lived for many years in modest lodgings before acquiring a house on Prinzessinstraße in 1783. This home contained a study filled with books, a dining room for his lunches, and simple but orderly furnishings — a reflection of his regimented life.

Historical Timeline

1724Naissance d'Emmanuel Kant à Königsberg, en Prusse-Orientale.

1740Avènement de Frédéric II de Prusse, dit le Grand, monarque éclairé protecteur des arts et des sciences.

1746Kant publie son premier ouvrage, Pensées sur la véritable estimation des forces vives, après la mort de son père.

1755Kant obtient son habilitation à l'université de Königsberg et publie son Histoire naturelle universelle et théorie du ciel.

1756Début de la guerre de Sept Ans ; Königsberg est occupée par les Russes de 1758 à 1762.

1762Publication du Contrat social et de l'Émile de Rousseau, ouvrages qui marquent profondément Kant.

1770Kant est nommé professeur titulaire de logique et de métaphysique à l'université de Königsberg.

1776Déclaration d'indépendance des États-Unis d'Amérique, inspirée par les idées des Lumières.

1781Publication de la Critique de la raison pure, œuvre majeure qui révolutionne la philosophie occidentale.

1784Kant publie Qu'est-ce que les Lumières ?, texte fondateur définissant l'esprit des Lumières.

1789Début de la Révolution française, que Kant accueille d'abord avec enthousiasme.

1793Kant publie La Religion dans les limites de la simple raison, ce qui lui vaut la censure du roi Frédéric-Guillaume II.

1795Publication du Projet de paix perpétuelle, texte visionnaire sur la coopération internationale entre États.

1804Mort de Kant à Königsberg le 12 février, après plusieurs années de déclin physique.

Period Vocabulary

Aufklärung — German word for the Enlightenment, the 18th-century intellectual movement advocating the use of reason and the emancipation of the individual.

Categorical imperative — Kant's fundamental moral principle: an action is morally good only if one can will that its maxim become a universal law.

Noumenon — In Kant's philosophy, the thing-in-itself as it exists independently of our perception, as opposed to the phenomenon, which is the thing as it appears to us.

Metaphysics — Branch of philosophy that studies the first principles of reality, existence, and knowledge, beyond sensory experience.

Pietism — A movement within Lutheran Protestantism, strongly present in Prussia, emphasizing personal piety and moral rigor. Kant's family was deeply influenced by it.

Privatdozent — An unsalaried university lecturer in the German academic system, paid directly by the students who attended their courses. Kant held this position for fifteen years.

Enlightened despotism — A form of 18th-century government in which an absolute monarch, such as Frederick II of Prussia, adopted Enlightenment ideas to modernize the state.

Cosmopolitanism — The idea that every human being is a citizen of the world. Kant advocated for a cosmopolitan right guaranteeing universal hospitality among peoples.

Critical philosophy — Kant's distinctive philosophical method, consisting in examining the conditions of possibility and the limits of human knowledge before making any metaphysical claims.

Understanding — The faculty of the mind that enables thought and the formation of concepts. In Kant, the understanding organizes sensory data through a priori categories.

Gallery

Immanuel Kant

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Immanuel Kant

Immanuel Kant (1724-1804)

Immanuel Kant by Johann Christoph Frisch

Kant Kaliningrad

Bust of Emmanuel Kant

Immanuel Kant portrait c1790

Christelijke encyclopædie voor het Nederlandsche volk 3-318

The science of universal history: its method and its relation to the physical sciences

Visual Style

Esthétique austère et raffinée de la Prusse des Lumières, entre intérieurs studieux éclairés à la bougie et paysages brumeux de la Baltique, dans des tons sobres de bleu nuit, gris et ivoire.

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AI Prompt

Late 18th-century Prussian academic aesthetic. Muted, austere color palette dominated by deep navy blue, charcoal grey, parchment ivory and warm candlelight amber. Architectural elements of Baltic Gothic and modest Baroque—red brick cathedral, narrow cobblestone streets, half-timbered faculty houses. Interior scenes lit by candlelight with heavy wooden bookshelves, leather-bound volumes, manuscripts, and astronomical instruments. A sense of disciplined order and intellectual clarity. Portraits inspired by Anton Graff's style—restrained, dignified, with careful attention to fabric textures of wool coats and white cravats. Atmospheric perspective showing misty riverbanks and rows of linden trees under a pale northern sky.

Sound Ambience

L'atmosphère sonore paisible de Königsberg au XVIIIe siècle : cloches de la cathédrale, plume grattant le papier, pas réguliers sur les pavés et bruissement des tilleuls le long de la rivière Pregel.

AI Prompt

Ambient sounds of an 18th-century Prussian university town: distant church bells tolling the hour from a Gothic cathedral, the slow creak of a wooden desk chair, a quill pen scratching methodically on thick paper, the soft ticking of a pocket watch. Outside, cobblestone footsteps of a solitary walker on a tree-lined path along a river, rustling linden leaves in a gentle Baltic breeze, the faint murmur of the Pregel river below. Birdsong of northern European species—thrushes, finches. Occasionally, the distant rumble of a horse-drawn carriage on stone streets, muffled voices of university students crossing a courtyard, and the gentle clink of porcelain cups during a midday philosophical gathering.

Portrait Source

Wikimedia Commons — domaine public — Becker — 1768