Immanuel Kant

1724 - 1804 | German Philosopher & Pioneer of Critical Philosophy

Early Life & Background

Born in Königsberg, Prussia (now Kaliningrad, Russia), Kant was the fourth of nine children in a devoutly Pietist family. His father was a harness-maker, and the family emphasized moral discipline and religious devotion. Kant attended the University of Königsberg, where he studied philosophy, mathematics, and physics. Remarkably, he would spend his entire life in Königsberg, never traveling more than 100 miles from his birthplace.

The Pre-Critical Period

For the first part of his career, Kant worked as a private tutor and later as a lecturer at the University of Königsberg. During this "pre-critical" period, he was influenced by rationalist philosophers like Leibniz and Wolff. However, reading David Hume's skeptical philosophy "awakened him from his dogmatic slumber," leading him to question whether pure reason could provide certain knowledge about the world.

The Critical Philosophy

At age 57, Kant published the "Critique of Pure Reason" (1781), launching his "critical period" and revolutionizing philosophy. He argued that we can never know things "in themselves" but only as they appear to us through the structures of our mind. This "Copernican revolution" in philosophy showed how synthetic a priori knowledge is possible while limiting reason to make room for faith and morality.

Major Works

• "Critique of Pure Reason" (1781/1787) - Limits and conditions of knowledge
• "Critique of Practical Reason" (1788) - Moral philosophy and freedom
• "Critique of Judgment" (1790) - Aesthetics and teleology
• "Groundwork for the Metaphysics of Morals" (1785)
• "What is Enlightenment?" (1784) - Essay on intellectual freedom

Moral Philosophy

Kant developed a duty-based ethical system grounded in the categorical imperative: "Act only according to that maxim whereby you can at the same time will that it should become a universal law." He argued that moral worth comes not from consequences but from acting from duty and good will. This deontological approach emphasizes human dignity, autonomy, and the inherent worth of rational beings.

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

Personal Life & Habits

Kant was famous for his rigid daily routine - so punctual that neighbors could set their clocks by his afternoon walk. He never married, lived a simple life, and was known for his wit and hospitality at dinner parties. Despite his systematic philosophy, he was sociable and enjoyed conversation, good food, and company. His methodical lifestyle allowed him to produce an enormous body of work while maintaining his teaching duties.

Political & Religious Thought

Kant advocated for republican government, international peace, and gradual reform rather than revolution. His essay "Perpetual Peace" envisioned a federation of republics that would end war. In religion, while personally devout, he argued that God's existence cannot be proven through pure reason but is a necessary postulate of practical reason and moral life.

Lasting Legacy

Kant's critical philosophy fundamentally reshaped Western thought, influencing virtually every subsequent philosophical movement from German Idealism to contemporary analytic philosophy. His moral philosophy remains central to ethical theory, while his political ideas influenced democratic thought and international law. His synthesis of rationalism and empiricism, his defense of human dignity and autonomy, and his vision of enlightenment as humanity's emergence from self-imposed tutelage continue to shape debates about knowledge, morality, and human freedom.