Modern Philosophy

In a world where good actions produce disastrous results and base actions yield prosperity, what can still be called good without qualification? Immanuel Kant answered that question with a clarity that has unsettled moral philosophy for more than two centuries: only the good will deserves to be called an unconditioned good. Not talent, not courage, not even happiness — for all of these can be turned toward wicked ends. Only the will that acts out of pure respect for the moral law, independently of its consequences, possesses moral worth in itself. From this inaugural insight, Kant constructed, in the Groundwork of the Metaphysics of Morals (1785) and the Critique of Practical Reason (1788), the most ambitious and most contested ethical architecture of modernity. ...

There is a philosopher who, writing in Latin in a small house in The Hague in the seventeenth century, formulated one of the most radical worldviews Western philosophy has ever produced — and did so in the unlikely form of a treatise of geometry. That philosopher is Baruch (Bento) Spinoza (1632–1677), and the treatise is the Ethics demonstrated in geometrical order, published posthumously in the year of his death. In a little over two hundred pages, organized into definitions, axioms, propositions, and demonstrations, Spinoza proposes simultaneously a metaphysics of the absolute, a theory of human affects, a psychology of knowledge, and an ethics of freedom. His influence runs across three centuries — Lessing, Goethe, Hegel, Marx, Nietzsche, Deleuze, Antonio Damasio — and his name still functions, in the history of philosophy, as a cipher for an intellectual decision: thinking God, nature, and the human being as expressions of a single reality. ...

There are few moments in the history of philosophy that can rival, in sheer radicality and consequence, the one in which René Descartes, secluded in his Dutch stove-heated room, discovered that the very act of doubting contains within itself an unshakeable certainty: whoever doubts, thinks — and whoever thinks, exists. The cogito — formulated in slightly different ways across three major works — became not merely the starting point of Cartesian philosophy but the founding act of all modern philosophy. Through it, human subjectivity installed itself at the centre of philosophical inquiry and has remained there, in various guises, for four centuries. ...

Few philosophical traditions traverse the history of Western thought as persistently as idealism. From Plato’s Theory of Forms to Hegel’s absolute system, passing through Berkeley’s immaterialism and Kant’s critical philosophy, the claim that reality is ultimately constituted or conditioned by thought, mind, or spirit resurfaces in radically diverse guises. This article examines the major strands of philosophical idealism — their premises, arguments, and internal differences — and the decisive critiques levelled against them by Marx, Russell, and Moore. ...

Few concepts have traversed the history of Western philosophy with such persistence — and so many metamorphoses — as substance. From the Greek ousia to the Latin substantia, from Aristotelian form to the Leibnizian monad, from Cartesian res cogitans to Locke’s unknown substratum, this term has served as the axis for the most decisive metaphysical questions: What truly exists? What persists through change? What is a thing apart from its properties? ...

There is an experience nearly all of us have had and very few can explain: listening to a piece of music — a Beethoven symphony, a Mozart adagio, an unexpected chord in some ordinary song — and feeling something that cannot be put into words. It is not joy, not sadness, not any nameable emotion. It is as if the music touched a layer of our existence that lies beneath language, beneath thought, beneath everything we call “self.” Why does this happen? Why does music move us in a way that painting, poetry, and sculpture — however beautiful — can never quite replicate? ...

Friedrich Nietzsche died in 1900, yet he seems to have written his books for the twenty-first century. The German philosopher who proclaimed “God is dead” was not celebrating — he was issuing a bleak diagnosis of what happens when an entire civilization loses the foundation that organized its values. In today’s world, that diagnosis resonates with unsettling precision: we live in an era of meaning crisis, of collapsing values, of diffuse nihilism concealed beneath layers of digital entertainment, social media, and consumerism. Nietzsche did not merely predict this scenario — he described in detail what was coming. ...

Adam Smith Scottish moral philosopher and economist, considered the father of modern political economy. A central figure of the Scottish Enlightenment and close friend of Hume. His work combines sentiment-based ethics with market theory. Before he became known as a theorist of economics, Smith was a professor of moral philosophy at the University of Glasgow, and it is from that chair that the core of his thought takes shape. In The Theory of Moral Sentiments (1759) he begins with a characteristically Enlightenment question: how do beings driven by their own interests come to make moral judgments and to care about others? His answer lies in sympathy — not a feeling of pity, but the capacity to imagine oneself in another’s situation — and in the “impartial spectator,” an inner tribunal that leads us to judge our own conduct as a well-informed and disinterested observer would. For Smith, morality derives neither from abstract reason nor from external commandments, but from this web of mutual affections and reciprocal judgments that sustains social life. ...

Baruch Spinoza (Benedict of Spinoza) Born in Amsterdam in 1632, into a family of Sephardic Jews of Portuguese origin who had fled the Inquisition, Baruch Spinoza received a rabbinic education, but his ideas soon put him on a collision course with the community: in 1656 he was subjected to a herem (excommunication) of rare severity. He declined chairs and honors to preserve his independence of thought and supported himself humbly by grinding optical lenses. He died young, in 1677, and his principal works — among them the Ethics — were published only after his death. He is regarded as the most radical of the seventeenth-century rationalists. ...

Blaise Pascal French mathematician, physicist and philosopher. A precocious genius (invented the mechanical calculator at age 19); converted to Jansenism after his “night of fire” (1654). His philosophy is an existential wager and a confrontation with the reason of the libertines. Key Concepts The wager (Pascal’s wager): pragmatic argument about belief in God. If God exists and you believe — infinite gain; if he does not exist and you believe — finite loss. If he exists and you do not believe — infinite loss. Prudent reason bets on God — even without rational proof “The heart has its reasons which reason knows nothing of”: there is an order of the heart — intuition, love, feeling — irreducible to the demonstrative logic of Descartes Misery and grandeur of man: man is a roseau pensant (thinking reed) — fragile as nature, but his greatness lies in thinking; more noble than the universe because he knows that he dies The two infinities: between the great infinity (cosmos) and the small infinity (atom), man stands in the middle — without firm foundation either in sciences or in metaphysics Diversion (divertissement): man flees from confrontation with himself through agitation — boredom reveals the human misery that diversion hides. Critique of social superficiality Critique of Cartesianism: Descartes’ method is useful in the sciences, but illusory as a foundation for faith or morality; “Descartes useless and uncertain” Jansenism: Catholic current that emphasized the irresistible grace of Augustine; Pascal defended Port-Royal in the Provincial Letters against the Jesuits Influenced by Saint Augustine — grace, sin, predestination Montaigne — skepticism, human misery (point of departure and adversary) Descartes — rationalism (critique) Ancient Pyrrhonism — skepticism as apologetic weapon Influenced Kierkegaard — wager, paradox, subjectivity of faith Existentialism — anguish and human condition Modern Christian apologetics Decision theory and game theory (wager as precursor) Works Provincial Letters (1656–1657); Pensées (posthumous, 1670 — fragments of an unfinished apologetic); Treatise on the Arithmetic of the Triangle (1654). ...

David Hume A central figure of the Scottish Enlightenment, David Hume was born in Edinburgh in 1711. While still very young he published his Treatise of Human Nature (1739–40), a work that, in his own words, “fell dead-born from the press” and would be recognized only much later. His reputation as a skeptic in matters of religion cost him the university chairs he sought; he made his living as a librarian, a diplomatic secretary, and above all as a highly successful essayist and historian. A man of serene and amiable temperament — “le bon David” — he died in 1776, facing death with the tranquility of a sage. ...

Denis Diderot Denis Diderot (1713–1784) is one of the most complex and prolific figures of the French Enlightenment. The son of a cutler from Langres, he studied in Paris, lived through decades of turbulent intellectual life, and was the principal architect of the Encyclopédie ou Dictionnaire raisonné des sciences, des arts et des métiers (1751–1772), which he co-edited with Jean le Rond d’Alembert. The project brought together the greatest minds of the century — Voltaire, Rousseau, Montesquieu, Turgot — with the aim of gathering, systematizing, and disseminating human knowledge in the service of reason and the critique of superstition. Hounded by royal censorship and the Church, the enterprise stands as the greatest monument of the encyclopedist spirit and the Enlightenment faith in the transformative power of knowledge. ...

Francis Bacon “Father of Empiricism” and of modern experimental science. Lord Chancellor of England; fell into disgrace due to corruption. His project was to renew knowledge by replacing Aristotle’s Organon with a new inductive-experimental method. Bacon writes at the transition from the Renaissance to modernity, at a time when natural philosophy was still dominated by the Scholastic Aristotelianism transmitted through the universities. Against this tradition, he diagnoses that inherited knowledge had become sterile: highly skilled at disputing and classifying, yet incapable of producing useful works or of extending human dominion over nature. The central problem, for Bacon, was not a lack of intelligence but the lack of a correct method. Aristotle’s syllogistic logic, on his reading, merely rearranges the confused notions already contained in words, without guaranteeing that those notions correspond to things; it therefore serves to win debates, not to discover new truths about the world. In response, Bacon proposes a “Great Instauration” (Instauratio Magna) of knowledge — a fresh start grounded in ordered experience and methodical observation rather than in the authority of the ancients. ...

Friedrich Wilhelm Joseph Schelling The most versatile of the German idealists; his thought passed through multiple radically distinct phases. He directly influenced Romanticism and anticipated Existentialism. Born in Leonberg, Württemberg, in 1775, Schelling studied at the Tübingen Stift alongside Hegel and Hölderlin, where enthusiasm for the French Revolution and Kantian philosophy shaped an entire generation. By his early twenties he was already publishing works of remarkable originality, and in 1798 he accepted a professorship in Jena — then the intellectual epicenter of German Idealism and Romanticism. That milieu made him a direct interlocutor of Fichte, Goethe, and the Schlegel brothers, cementing his reputation as the most promising philosopher of his age. ...

Georg Wilhelm Friedrich Hegel Georg Wilhelm Friedrich Hegel was born in Stuttgart in 1770 and studied at the Tübingen seminary alongside Hölderlin and Schelling. A young enthusiast of the French Revolution, he saw in Napoleon — whom he glimpsed on horseback at Jena in 1806 — the “world-soul” on the march. After years as a private tutor, journalist, and school headmaster, he reached the chairs of Heidelberg and, above all, Berlin, where he became the most influential philosopher in the Germany of his time, until his death in 1831. His work is the most ambitious system in the history of philosophy: logic, nature, spirit, history, art, and religion articulated as moments of a single process. ...

George Berkeley An Irish philosopher born in 1685 and later the Anglican Bishop of Cloyne, George Berkeley produced his most important philosophical works while still very young, before the age of thirty. A man of faith and action, he even crossed the Atlantic with a project to found a college in Bermuda for the American colonies. He is remembered as the second great name of British empiricism, between Locke and Hume — and the most surprising of the three, for pushing empiricism to a radical conclusion: that matter does not exist. ...

Gottfried Wilhelm Leibniz Born in Leipzig in 1646, Gottfried Wilhelm Leibniz was the last great universal sage: at once philosopher, mathematician, logician, physicist, jurist, historian, and diplomat. He invented — independently of Newton — the infinitesimal calculus, whose notation we still use, conceived the binary arithmetic that underlies computing, and designed calculating machines. He spent much of his life in the service of the House of Hanover and died in 1716, leaving a body of work scattered across thousands of letters and few published books. Philosophically, he sought the great reconciliation of modern science, the metaphysical tradition, and faith. ...

Immanuel Kant Born in Königsberg, in East Prussia, in 1724, and never having strayed from his native city, Immanuel Kant led the methodical life of a university professor — so regular, tradition holds, that his neighbors set their clocks by his daily walk. It was, in his own words, the reading of Hume that “awakened him from his dogmatic slumber” and led him into a long decade of silence, at the end of which, already 57 years old, he published the monumental Critique of Pure Reason (1781). His work both closes and refounds Modernity, mediating the dispute between the rationalism of Descartes and the empiricism of Hume. ...

Jean-Jacques Rousseau Born in Geneva in 1712 and motherless from birth, Jean-Jacques Rousseau was largely self-taught and led a wandering life before rising to prominence in Paris, where he kept company with the Encyclopedists — from whom he would later break dramatically. Recognition came in 1750, when he won the Dijon Academy’s competition with a discourse that already announced his most provocative thesis: that the arts and sciences, far from improving humanity, corrupt morals. Persecuted after the publication of Emile, condemned and forced into exile, he ended his life tormented, in 1778, leaving behind the Confessions. He is the great critic of the Enlightenment from within the Enlightenment itself. ...

Johann Gottlieb Fichte First post-Kantian to overcome the thing-in-itself. Founder of German Idealism; first rector of the University of Berlin (1811). The Addresses to the German Nation (1808) made him a symbol of German cultural nationalism. Of humble origins, Fichte came to philosophy through his reading of Kant, which he described as an intellectual liberation. His first work, published anonymously in 1792, was taken by the public to be a writing of Kant himself; once the misunderstanding was cleared up, his reputation was secured, and in 1794 he took the chair of philosophy at Jena, then the most vibrant center of German thought. There he developed the Doctrine of Science (Wissenschaftslehre), an attempt to refound the whole of critical philosophy upon a single unconditioned principle — the Ego — and to eliminate the dogmatic residue that, in his view, the Kantian thing-in-itself still retained. ...