By 1784, the movement known as the Enlightenment was virtually dead in Germany. The Leibniz-Wolffian rationalism of earlier decades would not survive the century. Moses Mendelssohn, its clearest expositor, would die in 1785, embroiled in debate about the Spinozism of his friend Gotthold Ephraim Lessing. Yet, in 1784, Mendelssohn published in the Berlinische Monatsschrift an essay in which he answered the question: “What is Enlightenment?” In the next issue, another answer to the same question was published by Mendelssohn’s younger contemporary and associate Immanuel Kant (1724–1804), and yet while Kant’s answer clearly underlines the themes of the period, it is written by a philosopher whose work and whose thinking had already superseded it. To be sure, Kant would never abandon the themes of rationality and freedom; they are the core of his thinking. But in 1781 he had already published a work that dramatically altered the terms of discussion. Kant and the German Romantics—Johann Gottfried Herder, Johann Georg Hamann, Novalis, and others—set the Enlightenment and dogmatic rationalism to rest in the 1780s and 1790s, and yet in 1784 Kant’s differences with the past were perhaps hard to discern.
Kant lived all of his life in or near Königsberg, in East Prussia, where he was born on April 22, 1724. His father was a harnessmaker; the family were devoted Pietists, committed to moral conduct and inner purity as the primary modes of religious worship. In his youth Kant learned to dislike the trappings of religious ritual and formality. In 1750 he enrolled at the University of Königsberg, where he studied with Martin Knutzen, a Leibniz-Wolffian who introduced him to mathematics, physics, and astronomy, as well as logic and metaphysics. After leaving the university, Kant served as a private tutor and returned to town in 1754, when he published the Universal Natural History and Theory of the Heavens. It was an attempt, now considered original, to apply Newtonian physics and its principles to the problem of the generation of the solar system.
By 1755 Kant was qualified as a Privatdozent (lecturer) at the university, where he lectured on mathematics, philosophy, scientific subjects, and much more. Until this time Newton and the new science, along with the current rationalist philosophy, were the major influences on Kant. In 1762, however, another powerful influence was added to them. When Kant received his copy of Rousseau’s Émile, for two days he interrupted his rigorous routine of afternoon walks in order to finish reading the book. It was Rousseau who taught him “to honor man” and to make the cultural and political defense of human dignity his primary task. In the same year Kant submitted an essay to the Berlin Academy on the subject whether the principles of natural theology and morality can be proven like those of geometry. Although Mendelssohn’s essay won the prize, both were published together in 1764.
In 1770 the University of Königsberg appointed Kant Professor of Logic and Metaphysics, and Kant delivered his Inaugural Dissertation, in which he first adumbrated the “critical” philosophy that would shape the remainder of his career. The following decade Kant published nothing. He was deep at work on his classic, the Critique of Pure Reason, which would appear in 1781. This was followed by a flood of publications: the Prolegomena to Any Future Metaphysics, the revisions of the First Critique in 1787, the Critique of Practical Reason in 1787, the Critique of Judgment in 1790, and the Grounding for the Metaphysics of Morals in 1785. In this last, extraordinary work, Kant presented his defense of rational morality, of autonomy, and of human dignity in a book that is one of the classic texts of Western moral philosophy.
During these years Kant’s life was filled with teaching, writing, conversation, and occasional public controversy. In his public writings and discussions, he defended the rule of law, argued against the right of rebellion, and yet praised the French Revolution. In 1793 Kant published Religion within the Limits of Reason Alone and with this strange and difficult work drew the severe censure of Frederick William II and his royal cabinet. Kant was forbidden to write or lecture on any religious subject. He weighed the dilemma, to heed his sovereign or to acknowledge his deepest convictions, and on October 12, 1794, Kant chose to submit as an obedient subject. It was an act that generated widespread criticism.
In 1795 Kant published To Perpetual Peace, his first work after the ban and his defense of an international league of nations. The book was especially praised in France; in it Kant gives fullest expression to his political views. In 1797 he chose no longer to lecture but continued to write until his death, on February 12, 1804. Heine once said that no one could write a life of Kant because Kant had no life. This is a harsh judgment. Having read Plato since 1768, Kant had assimilated the Socratic commitment to truth. His life was a quest for it, and hence to write the tale of that life would be to write the story of his thought, a story of reason, freedom, and human dignity.
Kant’s critical philosophy is a watershed in modern metaphysics, epistemology, and moral theory. His goal was to acknowledge the supremacy of science, to revise the role of metaphysics, and yet to ground morality in rationality. All subsequent Western philosophy and moral theory is indebted to his work and to the strategies which he employed for confronting the challenges of science, philosophy, ethics, and religion in the modern world.
Recommended Readings
Allison, Henry. Idealism and Freedom. Cambridge: Cambridge University Press, 1996.
Allison, Henry. Kant’s Theory of Freedom. Cambridge: Cambridge University Press, 1990.
Arendt, Hannah. Lectures on Kant’s Political Philosophy. Chicago: University of Chicago Press, 1982.
Beck, Lewis White. A Commentary on Kant’s Critique of Practical Reason. Chicago: University of Chicago Press, 1960.
Beiser, Frederick. Enlightenment, Revolution, & Romanticism: The Genesis of Modern German Political Thought, 1790–1800. Cambridge, Mass.: Harvard University Press, 1992.
Booth, James. Interpreting the World: Kant’s Philosophy of History and Politics. Toronto: University of Toronto Press, 1987.
Guyer, Paul. The Cambridge Companion to Kant. Cambridge: Cambridge University Press, 1992.
Guyer, Paul. Kant and the Experience of Freedom. Cambridge: Cambridge University Press, 1993.
Herman, Barbara. The Practice of Moral Judgment. Cambridge, Mass.: Harvard University Press, 1993.
O’Neill, Onora. Acting on Principle. New York: Columbia University Press, 1975.
O’Neill, Onora. Constructions of Reason: Explorations of Kant’s Practical Philosophy. Cambridge: Cambridge University Press, 1989.
Paton, H. J. The Categorical Imperative, third ed. London: Hutcheson, 1958.
Reiss, Hans (ed.). Kant’s Political Writings. Cambridge: Cambridge University Press, 1970.
Schneewind, J. B. The Invention of Autonomy. Cambridge: Cambridge University Press, 1998.
Wolf, Robert Paul. The Autonomy of Reason. New York: Harper & Row, 1973.
Wolf, Robert Paul. In Defense of Anarchism. New York: Harper & Row, 1970.
Wolf, Robert Paul (ed.). Kant. Garden City: Doubleday, 1967.
Wolf, Robert Paul (ed.). Kant’s Foundation and Critical Essays. Indianapolis: Bobbs-Merrill, 1969.
Wood, Allen. Kant’s Ethical Thought. Cambridge: Cambridge University Press, 1999.
Wood, Allen. Kant’s Moral Religion. Ithaca: Cornell University Press, 1970.
Yovel, Y. Kant and the Philosophy of History. Princeton: Princeton University Press, 1968.