Articles

The Institut für Sozialforschung In 1923, the Institut für Sozialforschung (Institute for Social Research) was founded in Frankfurt am Main — the first independent Marxist research institution attached to a German university. Associated with the University of Frankfurt (today Goethe-Universität), the Institute would gather, over the following decades, thinkers who gave rise to what became known as the Frankfurt School and its Critical Theory. The term “Critical Theory” was used by the members themselves — particularly Max Horkheimer — to distinguish their project from “traditional theory” (positivist, oriented toward description and prediction) and from purely normative theory (prescribing without analyzing the conditions for realization). Critical Theory aims to unite social analysis with an emancipatory interest: to understand society from the contradictions it generates, contradictions that point toward the possibility of transformation. ...

Niccolò Machiavelli (1469–1527) is one of those rare names whose work divides the history of philosophy into a before and an after. Before him, political philosophy belonged to the genre of the “mirror of princes” — treatises that prescribed to rulers the classical moral virtues (prudence, justice, fortitude, temperance) and obedience to divine law. After him, politics became an autonomous domain, with its own logic, irreducible to morality or theology. This rupture is so decisive that many historians make the birth of modern political philosophy coincide with the writing of The Prince (1513). ...

What distinguishes a scientific theory from a myth, an ideology, or a metaphysical system? Why do we accept as knowledge what physics tells us, but not what astrology — or psychoanalysis, at least in its more speculative form — claims? These questions, simple at first glance, opened in the twentieth century one of the most consequential debates in contemporary philosophy. Its two central figures — Karl Popper and Thomas Kuhn — formulated answers that, far from reconciling, redrew the landscape of epistemology. ...

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. ...

Probably no philosophical text, in twenty-five centuries of Western tradition, has been more commented, paraphrased, glossed, and reinterpreted than the passage that opens Book VII of Plato’s Republic. In three pages of translation, Socrates asks Glaucon to imagine men chained from birth at the bottom of a cave, seeing only shadows projected on a wall — and proposes that this scene describes, with startling fidelity, the common condition of human beings. This is the Allegory of the Cave, and it is at once one of the most famous pieces of philosophy and one of the most systematically misunderstood. To read it rigorously, it must be situated in its context: it is the third of three articulated images — following the metaphor of the sun and the divided line — that constitute the core of Plato’s mature thought. ...

Why should we obey the State? What makes a law legitimate rather than a mere order imposed by force? In the history of Western philosophy, these questions found their first systematically modern formulation in the seventeenth and eighteenth centuries, with three thinkers who changed forever the vocabulary of politics: Thomas Hobbes, John Locke, and Jean-Jacques Rousseau. The three give radically different answers, but share a method: contractualism — the idea that political legitimacy must be thought from a hypothetical pact among free individuals. ...

“Does God exist?” is perhaps the oldest and most persistent question in philosophy. It has accompanied Western thought from the earliest Presocratics — when Xenophanes of Colophon (c. 570–c. 475 BC) criticized the anthropomorphism of Homer’s gods — to contemporary analytic debates on modal logic and Bayesian probability. And yet, posed in these terms, the question conceals a trap. For before asking whether God exists, one must ask what it means, for God, to exist. Here a decisive distinction opens up — one that separates philosophically rigorous theism from conceptual idolatry: the distinction between existing (existere) and being (esse). ...

Between the seventeenth and eighteenth centuries, a quiet transformation reshaped the nature of political power in the West. The sovereign, once defined by the prerogative to kill — to take the lives of disobedient subjects — began exercising a radically new form of authority: administering, optimizing, and regulating the life of populations. Michel Foucault called this shift biopower, and in doing so inaugurated one of the most productive conceptual fields in contemporary political philosophy. ...

No philosophical movement of the twentieth century shaped culture, literature, and our self-understanding as profoundly as existentialism. Born amid the wreckage of two world wars, the collapse of metaphysical certainties, and the crisis of traditional institutions, it placed at the heart of philosophy what the great systems had overlooked: the concrete, singular, unrepeatable existence of each individual. Existentialism is not a school with a uniform set of doctrines. It is better described as a constellation — a cluster of thinkers who, through diverse and sometimes conflicting paths, converge on one conviction: philosophy must begin with lived experience, with anguish, freedom, and the finitude of the human being, rather than with logical abstractions or totalizing systems. ...

Few philosophers can claim to have changed, so deliberately and programmatically, the very purpose of human knowledge. Francis Bacon (1561–1626) did not merely propose one philosophical theory among many: he conceived a total reform of learning, a project intended to replace the Aristotelian tradition with a new method capable of generating useful, verifiable, and progressive knowledge. The title of his magnum opus — Novum Organum (1620) — announces, right on its cover, the scale of the ambition: a new instrument of thought, designed to supplant Aristotle’s ancient Organon, which had governed Western logic for nearly two millennia. ...

Few concepts have persisted across the entire history of philosophy with as much tenacity as justice. From fifth-century Athens to twentieth-century lecture halls, the question has remained essentially the same: what is just? The answers, however, vary dramatically — and it is precisely in that variation that the philosophical interest lies. This article traces the major landmarks in Western reflection on justice, from Socrates’ confrontation with Thrasymachus to the contemporary theories of Amartya Sen and Martha Nussbaum. ...

Michel Eyquem de Montaigne (1533–1592) is one of those rare thinkers whose influence is measured not by the construction of a philosophical system but by the invention of a form. By creating the essay — a word he coined himself, from the French essai, meaning attempt or trial — he inaugurated a way of thinking that refuses any claim to final truth and makes the thinking subject both the object and the instrument of inquiry. His Essais, published between 1580 and 1595, remain among the most widely read texts in Western literature, and their philosophical significance has only grown with time. ...

Few questions run through the history of philosophy as persistently as this one: what is truth? From Parmenides to Foucault, every era has reformulated this inquiry according to its own assumptions about reason, language, being, and power. This article traces the major stations of that journey — from Greek alétheia to the contemporary crisis of post-truth — not as a mere chronology, but as a map of the tensions that still define philosophical thought. ...

Mário Ferreira dos Santos (1907–1968) is, in sheer scale of output, the largest systematic philosophical project ever attempted in Brazil. His Encyclopaedia of Philosophical and Social Sciences, planned in more than fifty volumes, is an undertaking without parallel in Brazilian intellectual history — and rare even in the international context of the 20th century, in which academic philosophy progressively abandoned systematic form. Whatever limitations one may identify in the work — and they exist —, Mário Ferreira’s project deserves serious academic examination: for its scope, its theoretical ambition and the singular position it occupies between Thomist scholasticism, Pythagoreanism, phenomenology and the German dialectical tradition. This article presents the life, the work and the central doctrine — Concrete Philosophy — with critical rigour and without hagiography. ...

In 1996, the Brazilian philosopher Olavo de Carvalho published a short, dense book titled Aristóteles em Nova Perspectiva: Introdução à Teoria dos Quatro Discursos (Aristotle in a New Perspective: Introduction to the Theory of the Four Discourses). Regardless of the controversies surrounding the author as a public figure, this book represents his most philosophically articulate contribution and deserves to be examined on its own terms. Its central thesis — that Aristotle’s Organon, together with the Rhetoric and the Poetics, forms a unified hierarchy of four types of discourse — engages real problems in the history of philosophy and shares ground with contemporary neo-Aristotelian readings by Pierre Aubenque, Enrico Berti, Alasdair MacIntyre and Martha Nussbaum. ...

There are three names that every history of Western philosophy is bound to utter in this order: Socrates, Plato and Aristotle. The sequence is not arbitrary. It is a chain of direct transmission — Socrates was Plato’s teacher; Plato was Aristotle’s teacher — which, in little more than a century, turned Athens into the centre of rational thought in the ancient world and fixed the problems, the methods and the vocabulary that philosophy would use for the next two thousand years. ...

The history of Western philosophy can be read, without exaggeration, as the history of the forgetting of being. This is the thesis that runs through the entire work of Martin Heidegger (1889–1976) — arguably the most influential and most controversial philosopher of the twentieth century. Being and Time (1927), his magnum opus, did not propose yet another theory about the world, the mind, or morality: it proposed that philosophy as a whole — from Plato to Nietzsche — had left its most fundamental question unthought: what does it mean to be? ...

Among all the philosophical schools of Antiquity, none exercised so prolonged and so diverse an influence as Stoicism. Founded in Athens around 300 BCE by Zeno of Citium, Stoicism spanned five centuries, shaped Roman law, infiltrated early Christianity, and resurfaced powerfully in the Renaissance, the Enlightenment, and — more recently — in cognitive-behavioral therapy and philosophical self-help movements. The reason for this longevity is simple: Stoicism offers a coherent and practicable answer to the most urgent question of human existence — how to live well in a world we do not control. ...

If medieval philosophy had to be represented by a single name, that name would be Thomas Aquinas (1225–1274). Dominican friar, theologian, and philosopher, Aquinas undertook the most ambitious intellectual synthesis of the Middle Ages: harmonizing the philosophy of Aristotle — newly rediscovered in the Latin West through Arabic and Greek translations — with Christian theology. The result was two monumental Summae and dozens of commentaries, disputed questions, and opuscula that shaped Catholic theology, natural law theory, political ethics, and Western metaphysics for centuries. ...

Sigmund Freud (1856–1939) never considered himself a philosopher — and took pains to mark the distance between psychoanalysis, which he intended as a science, and philosophical speculation. Yet few twentieth-century thinkers exercised as profound an influence on philosophy. The discovery of the unconscious as the determining agency of psychic life struck a decisive blow against the image of the rational subject inherited from the Enlightenment. If Copernicus removed the Earth from the center of the universe and Darwin removed humanity from the center of biological creation, Freud dislodged the conscious ego from the center of mental life — the third “narcissistic wound” of humankind, as he called it. ...