Heraclitus's book does not survive; what remains are roughly 130 short sayings preserved as quotations by later authors such as Plato, Aristotle, Plutarch, Sextus Empiricus, Clement of Alexandria, Hippolytus and Diogenes Laertius. Modern editions number them according to Hermann Diels and Walther Kranz (DK), and the reference edition presents them in a fresh translation with commentary.
Genre
Philosophy
The Art of War is a short treatise of thirteen chapters, around six thousand Chinese characters, written as a sequence of terse sayings introduced by the formula 'Sun Tzu said'. It begins by declaring war a matter of life and death for the state, to be studied through five constant factors: the moral law that binds people to their ruler, heaven (weather and seasons), earth (terrain and distance), the commander's qualities, and method and discipline.
The Last Days of Socrates gathers four dialogues by Plato that together tell the story of Socrates' trial and death in Athens in 399 BCE: the Euthyphro, the Apology, the Crito and the Phaedo. In the Euthyphro, Socrates meets Euthyphro outside the court where Socrates must answer an indictment for impiety and corrupting the young.
The Meno opens without any scene-setting. Meno, a rich young Thessalian from Pharsalus who has studied with the orator Gorgias, asks Socrates whether virtue comes by teaching, by practice, by nature, or in some other way.
The Symposium is a framed dialogue about eros, memory and ascent. Apollodorus repeats what Aristodemus told him about a banquet at Agathon’s house after the poet’s tragic victory.
The Republic begins with a question that never stays small: what is justice, and is the just life happier than the unjust? Socrates meets Cephalus, Polemarchus, Thrasymachus, Glaucon and Adeimantus in the Piraeus.
This volume pairs one of Plato's most literary dialogues with two letters attributed to him. The Phaedrus takes place outside the walls of Athens, where Socrates, who rarely leaves the city, walks with the young Phaedrus along the river Ilissus and sits under a plane tree on a hot summer day.
The Statesman (Politikos) is one of Plato's late dialogues, usually dated to the 360s or 350s BC. It continues the conversation of the Sophist, held the day before: a visitor from Elea, a follower of Parmenides, has defined the sophist, and now, at Socrates' request, he undertakes to define the statesman or king.
Timaeus offers Plato's most elaborate cosmological account, framed by Socrates' wish to see the ideal city in motion and Critias's story of ancient Athens and Atlantis. Timaeus then delivers a likely story about the cosmos, not a demonstration with mathematical certainty.
De Anima asks what soul is by beginning with the observable powers of living things. Aristotle reviews earlier accounts from thinkers such as Democritus, Empedocles, Anaxagoras, and Plato, then rejects explanations that make soul either a wandering body, a harmony, or a separate passenger inside the organism.
This volume joins two treatises by Aristotle that together set out what scientific knowledge is and how the natural world is to be understood. The Posterior Analytics, in two books, belongs to the logical works later grouped as the Organon.
The Laws is Plato's last and longest dialogue, twelve books of conversation in which three elderly men design the constitution and legal code of a new city. On a midsummer day an unnamed Athenian Stranger walks from Knossos toward the cave and shrine of Zeus with Cleinias, a Cretan, and Megillus, a Spartan.
The Nicomachean Ethics asks what the human good is and how a life can be shaped toward it. Aristotle begins from the idea that every craft, inquiry and action aims at some good, and that the highest practical good is eudaimonia, often translated happiness or flourishing.
The Poetics is Aristotle's short treatise on the art of poetry, chiefly tragedy and epic, and the oldest surviving work of literary theory in the West. It opens by defining all poetry, together with music and dance, as imitation (mimesis), and by distinguishing the arts according to the medium of imitation (rhythm, language, melody), the objects imitated (people better than us, worse, or like us), and the manner (narration or enactment).
On Duties is Cicero's last philosophical work, written in the autumn of 44 BC, in the months after the murder of Julius Caesar, and addressed as a letter in three books to his son Marcus, then studying philosophy at Athens under the Peripatetic Cratippus. Cicero follows, with freedom, the Stoic Panaetius of Rhodes, whose treatise on duty (kathēkon, Latin officium) he adapts for a Roman reader, adding examples from Roman history and from his own career.
Letters from a Stoic selects from Seneca’s Moral Letters to Lucilius, a sequence of philosophical letters that turn daily life into training for freedom. Seneca writes as an older adviser to a younger friend, but the letters are also exercises for himself.
The Discourses and the Encheiridion preserve the teaching of Epictetus, a lame former slave who ran a school of Stoic philosophy at Nicopolis in western Greece in the early second century. Epictetus wrote nothing.
The Meditations, which Marcus Aurelius may have titled simply 'To Himself', is a private notebook of philosophical reflections written in Greek, probably during his military campaigns on the Danube in the 170s CE. It was not intended for publication and consists of twelve books of entries ranging from single sentences to short essays, often repeated and varied as exercises to fix principles in the mind.
The Enneads collect Plotinus's treatises as arranged by his student Porphyry into six groups of nine. They do not form a continuous textbook, but they return again and again to a metaphysical pattern: all reality proceeds from the One, through Intellect, to Soul, and the philosophical life is a movement of return toward unity.
On the Making of Man is Gregory of Nyssa's theological anthropology, written as an extended reflection on Genesis and the claim that human beings are made in the image of God. Gregory combines scriptural exegesis, Platonizing philosophy, and late antique physiology to ask why humanity is embodied, rational, sexual, mortal, and capable of divine likeness.
City of God is Augustine’s monumental argument that Rome’s disaster does not discredit Christianity and that human history must be understood through two loves. The immediate occasion is the sack of Rome by Alaric in 410, after which critics blamed Christians for weakening the old gods.
The Consolation of Philosophy is a prison dialogue between the condemned Boethius and Lady Philosophy, who appears at his bedside when he is sick with grief and self-pity. The work alternates prose and metre.
The Journey of the Mind into God is Bonaventure's compact map of contemplative ascent, written after meditation on Francis of Assisi's vision of the six-winged seraph at La Verna. The work is structured around six stages, corresponding to the seraph's wings, by which the mind rises through creation, the self, and the names of God before passing beyond conceptual mastery into ecstatic union.
The Summa Theologiae, traditionally called the Summa Theologica, is Aquinas's unfinished synthesis of Christian theology, written, as its prologue says, for beginners who were confused by the disorder and repetition of existing textbooks. It contains some 512 questions divided into about 2,600 articles, each built on the same disciplined form inherited from university disputation.
On Free Will, published in Latin at Basel in September 1524 as De libero arbitrio diatribe sive collatio (a discourse or comparison of passages concerning free will), is Erasmus's public answer to Martin Luther on the question of whether the human will has any part in salvation. Erasmus had long hesitated to write against Luther, whose criticism of abuses he partly shared, but by 1524 he was pressed by friends, princes and churchmen to declare himself, and he chose the one doctrine on which he thought Luther had gone furthest: Luther's statement of 1520 that free will after the Fall is a name without a reality.
The Bondage of the Will is Martin Luther's long Latin reply to Erasmus's On Free Will, published at Wittenberg in December 1525, fifteen months after Erasmus's book appeared. It was written in a crowded year: the Peasants' War had been fought and suppressed, the Elector Frederick the Wise had died, and Luther had married Katharina von Bora in June.
Institutes of the Christian Religion is John Calvin's ordered account of Christian doctrine, written to train readers in godliness and to show the King of France what his persecuted evangelical subjects actually believed. The library text opens with the Prefatory Address to Francis I, which pleads that the Reformers teach nothing new but the faith of Scripture and the early fathers, and with Calvin's Epistle to the Reader, dated Geneva, 1 August 1559, in which he says he was never satisfied until the work was set in its present order.
The Novum Organum ('new instrument') is the second and only substantially completed part of Bacon's projected Instauratio Magna, a six-part plan to rebuild human knowledge from its foundations. Its title throws down a challenge to the Organon, the collection of Aristotle's logical works that had governed university teaching for centuries.
The Discourse on the Method of Rightly Conducting One's Reason and Seeking Truth in the Sciences was published anonymously in Leiden in 1637 as a preface to three scientific essays, the Dioptrics, the Meteors and the Geometry. Descartes wrote it in French rather than Latin so that readers using their natural reason, including women, could judge it without scholastic training, and he presented it not as a treatise but as a history or fable of his own mind.
Meditationes de prima philosophia, published in Paris in 1641, compresses Descartes's metaphysics into six meditations, each imagined as a day's reflection by a solitary thinker seated by the fire in a dressing gown. The book was issued with six sets of Objections from learned readers (Caterus, Mersenne's circle, Hobbes, Arnauld, Gassendi and others) and Descartes's Replies, which are longer than the Meditations themselves; a second edition (Amsterdam, 1642) added the Jesuit Bourdin's Seventh Objections.
Les Passions de l'âme, published in Amsterdam and Paris in November 1649, was Descartes's last book and his fullest account of how mind and body interact in emotional life. It grew out of his correspondence with Princess Elisabeth of Bohemia, who in 1643 had asked him how an immaterial thinking soul could move a body, and who later pressed him on the regulation of grief and the good life.
The Sceptical Chymist is a philosophical dialogue in which Robert Boyle tests the two reigning theories of what bodies are made of: the four elements of the Aristotelians (earth, water, air and fire) and the three principles, or tria prima, of the Paracelsian chemists (salt, sulphur and mercury). Both schools appealed to the same evidence, the analysis of mixed bodies by fire.
A Theologico-Political Treatise (Tractatus Theologico-Politicus) was published anonymously in Latin in Amsterdam in 1670, under a false Hamburg imprint, by the Dutch philosopher Baruch Spinoza. Its title page announces its purpose: to show that freedom to philosophize can be granted without harm to piety or the peace of the commonwealth, and cannot be withheld without destroying both.
The Pensées ('Thoughts') are the fragments of an unfinished apology for the Christian religion, found after Pascal's death in 1662 as nearly a thousand notes, many on slips of paper threaded together in bundles. Pascal had planned a work that would first unsettle the complacent unbeliever (the honnête homme of polite society) by showing the misery and contradiction of the human condition, then show that Christianity alone explains that condition and offers its remedy.
Ethics Demonstrated in Geometrical Order is set out like Euclid: definitions, axioms, numbered propositions, proofs, corollaries and the discursive notes (scholia) where Spinoza speaks most freely. Its five parts lead from God to human blessedness.
Newton's Principia sets out the mathematical principles of natural philosophy and shows that the same laws can explain terrestrial motion and celestial order. The work begins with definitions of mass, quantity of motion, inertia, impressed force, centripetal force, absolute and relative space, and absolute and relative time.
Locke says in the Epistle to the Reader that the Essay began when five or six friends meeting in his rooms found themselves at a standstill over questions of morality and revealed religion, and he proposed that they first examine what objects human understanding is fitted to deal with. Nearly twenty years later the result was a long, patient survey of where ideas come from, how they combine, how words signify them and how far knowledge and probable belief can reach.
George Berkeley's Treatise Concerning the Principles of Human Knowledge, published in Dublin in 1710 when its author was a twenty-five-year-old fellow of Trinity College, argues that the material world, understood as an unthinking substance existing outside every mind, is a philosophers' invention. What exists are minds and the ideas they perceive; for sensible things, to be is to be perceived.
Hume subtitled his first book 'an attempt to introduce the experimental method of reasoning into moral subjects', and he meant it literally: as Newton had explained the heavens by a few observed principles, Hume would explain belief, emotion and morality by a few principles of the mind. Book I, Of the Understanding, begins by dividing all perceptions into vivid impressions and fainter ideas, and holds that every simple idea is copied from a prior impression.
Hume first published this book in 1748 as Philosophical Essays Concerning Human Understanding, and gave it its present title in 1758. It is his deliberate second attempt at the material of Book I of the Treatise, written, he said, so that the argument would no longer fail through its manner.
Modelled on Cicero's On the Nature of the Gods, Hume's Dialogues are narrated by Pamphilus, a young man, to his friend Hermippus, and report a conversation at the house of Pamphilus's tutor, Cleanthes. Three speakers debate not whether God exists, which all profess to accept, but what can be known of God's nature by reason.
Kant's first Critique asks whether metaphysics is possible as a science, and answers by examining reason's own powers before trusting any of its claims about God, the soul or the world as a whole. The first-edition preface describes human reason as burdened by questions it cannot dismiss and cannot answer, and the second-edition preface proposes a Copernican experiment: instead of assuming that knowledge must conform to objects, suppose that objects must conform to the forms of our knowing.
Kant's Grundlegung zur Metaphysik der Sitten (1785), translated by Abbott as Fundamental Principles of the Metaphysic of Morals, is a short book with a narrow and ambitious aim: to identify and establish the supreme principle of morality. It does not offer a full ethical system, which Kant postponed to the Metaphysics of Morals of 1797, but clears the ground by asking what must be true of moral obligation if it is to bind every rational being without exception.
Immanuel Kant's Critique of Practical Reason, published at Riga in 1788, is the second of his three Critiques. Where the first Critique limited what reason can know about God, freedom and the soul, this book argues that pure reason is practical by itself: it can determine the will without any help from desire, and in doing so it gives freedom, God and immortality a secure footing as matters of rational belief.
Medical Inquiries and Observations upon the Diseases of the Mind is often called the first American psychiatry textbook. Benjamin Rush gathers observations, classifications, causes, and treatments for mania, melancholy, hypochondria, derangement, moral faculties, memory, and related conditions.
Die Welt als Wille und Vorstellung, translated by Haldane and Kemp as The World as Will and Idea, is Arthur Schopenhauer's single, systematic statement of a philosophy that he claimed expressed one thought from four sides. It appeared in December 1818 (dated 1819) in four books with an appendix criticising Kant, and in 1844 he added a second volume of fifty supplementary chapters keyed to the first.
Hegel's Philosophy of Right (Grundlinien der Philosophie des Rechts) was written as a textbook for his Berlin lectures on law, ethics and the state. Its preface is dated June 1820, and the book appeared in Berlin late that year with 1821 on the title page.
On War (Vom Kriege) is an unfinished philosophical inquiry into the nature of war, written by a Prussian staff officer who had lived through the Napoleonic transformation of warfare. It is organised in eight books, but Clausewitz left a note in 1827 saying that only the first chapter of Book I satisfied him, and he was revising the whole when he died.
The Philosophy of History (Vorlesungen über die Philosophie der Geschichte) is the posthumous edition of the lectures on the philosophy of world history that G. W. F. Hegel gave five times at the University of Berlin between the winter of 1822-23 and that of 1830-31. Hegel never wrote it as a book.
A System of Logic, Ratiocinative and Inductive, was published in London in 1843 in two volumes and went through eight editions in John Stuart Mill's lifetime, the last revised in 1872. Of its six books, the third, Of Induction, is the longest and the most influential; the library text gives that book alone, from an 1882 American printing of the eighth edition.
Fear and Trembling: Dialectical Lyric appeared in Copenhagen on 16 October 1843 under the pseudonym Johannes de silentio, 'John of silence', the same day as Repetition. Its subject is Genesis 22, in which God commands Abraham to take his son Isaac to Mount Moriah and offer him as a burnt offering.
The Sickness Unto Death: A Christian Psychological Exposition for Upbuilding and Awakening was published in Copenhagen on 30 July 1849 under the pseudonym Anti-Climacus, with Kierkegaard named as editor. Its title comes from Jesus' words about Lazarus in John 11:4, 'This sickness is not unto death.' The introduction argues that for the Christian even death is not the sickness unto death, since there is hope beyond it; the true sickness unto death is despair, a condition in which one cannot die and cannot live, a perpetual dying without end.
Novum Organon Renovatum ('The New Organon Renewed') was published in London in 1858 by William Whewell, Master of Trinity College, Cambridge. It is the revised second part of his Philosophy of the Inductive Sciences (1840; second edition 1847), which for its third edition he divided into three books: the History of Scientific Ideas (1858), this volume on method, and On the Philosophy of Discovery (1860).
On the Origin of Species argues that species are not fixed, separately created kinds but populations changed over time by variation, inheritance, struggle, natural selection, and descent with modification. Darwin begins with variation under domestication, using pigeons, livestock, and cultivated plants to show how small differences can be preserved and accumulated.
Utilitarianism is a short defence of the ethical theory Mill inherited from Jeremy Bentham and his own father. It was first published in three instalments of Fraser's Magazine in 1861 and as a book in 1863.
The Birth of Tragedy from the Spirit of Music, published in 1872 when Nietzsche was a twenty-seven-year-old professor at Basel, argues that Greek tragedy arose from the union of two opposed artistic drives, which he names after the gods Apollo and Dionysus. The Apollonian is the drive toward clear form, measure and individuation, whose physiological analogue is the dream, in which every person is a perfect artist of images.
Illustrations of the Logic of Science is a series of six essays that Charles Sanders Peirce published in Popular Science Monthly between November 1877 and August 1878. Written for a general educated readership, they set out a theory of inquiry, a rule for clarifying the meaning of ideas, a frequency account of probability, and a three-part classification of inference.
The Gay Science, also translated as The Joyful Wisdom, is Nietzsche's book of convalescence, experiment, and dangerous cheerfulness. Its aphorisms and songs range across knowledge, art, women, morality, religion, science, friendship, self-creation, health, and style.
Thus Spoke Zarathustra: A Book for All and None is a philosophical prose-poem in four parts, written in the cadences of Luther's Bible. Its hero borrows the name of the ancient Persian prophet Zoroaster, whom Nietzsche chose because the first moralist should be the one to overturn morality.
Subtitled 'Prelude to a Philosophy of the Future', Beyond Good and Evil was Nietzsche's attempt to restate in plain argumentative prose, divided into 296 numbered sections and a closing poem, the ideas that Thus Spoke Zarathustra had put in prophetic form. The preface opens by supposing that truth is a woman and that dogmatic philosophers, with their clumsy seriousness, have never known how to win her.
On the Genealogy of Morality is Nietzsche's most sustained inquiry into the historical and psychological origins of moral values. In three treatises he asks where good and evil came from, how guilt and bad conscience developed, and what ascetic ideals do for priests, philosophers, artists, scientists, and sufferers.
The Antichrist is Nietzsche's most direct assault on Christianity as a moral and cultural force. It argues that Christianity reverses life-affirming values, sanctifies weakness, elevates pity, falsifies psychology, and turns resentment into virtue.
Twilight of the Idols is Nietzsche in compressed diagnostic form. Subtitled How to Philosophize with a Hammer, it tests inherited idols by sounding them for hollowness.
The Principles of Psychology is a two-volume, 1,400-page textbook that William James spent twelve years writing for Henry Holt's American Science Series. It sets out to treat psychology as a natural science of mental life, studying feelings, desires, cognitions and decisions together with their bodily conditions, while refusing to reduce the mind to physiology or to dissolve it into atoms of sensation.
Die Traumdeutung appeared in November 1899 with the date 1900 on its title page, and Freud regarded it as his most important book. Its central claim is that dreams are meaningful psychic acts that can be interpreted, and that every dream, properly analysed, proves to be the fulfilment of a wish.
Science and Hypothesis (La Science et l'hypothèse, Paris, 1902) is the first of Henri Poincaré's three books on the foundations of science, written by one of the leading mathematicians of his age for a general educated public. It asks how much of science is fact, how much is reasoning, and how much is choice.
The Varieties of Religious Experience: A Study in Human Nature collects the twenty Gifford Lectures on Natural Religion that William James delivered at the University of Edinburgh in 1901 and 1902. Instead of studying churches, creeds or theology, James studies personal religious experience as a psychologist, drawing on a large collection of first-person documents: diaries, autobiographies, letters and replies to questionnaires.
The Aim and Structure of Physical Theory (La Théorie physique: son objet et sa structure) was published in Paris in 1906 by Pierre Duhem, professor of theoretical physics at Bordeaux, after appearing as a series of articles in the Revue de philosophie. A second edition (1914) added two essays, 'The Physics of a Believer' and 'The Value of Physical Theory'.
Pragmatism collects eight popular lectures that William James gave at the Lowell Institute in Boston in November and December 1906 and at Columbia University in January 1907. Published that year and dedicated to the memory of John Stuart Mill, the book presents pragmatism as both a method for settling disputes and a theory of what truth is.
The Problems of Philosophy is a short introduction to philosophy, chiefly to the theory of knowledge, written for a general reader. Russell opens by asking whether there is any knowledge so certain that no reasonable person could doubt it, and the fifteen chapters work toward a qualified answer.
Freud's late essay, in German Das Unbehagen in der Kultur ('the uneasiness in culture'), asks why civilized people, who have built so much for their own protection, are so often unhappy. It is written in eight short chapters in a conversational, self-questioning style.
The Logic of Scientific Discovery is Karl Popper's account of what makes a theory scientific and how scientific knowledge grows. It first appeared in Vienna in 1934, with the imprint date 1935, as Logik der Forschung, in a series edited by Moritz Schlick and Philipp Frank of the Vienna Circle.
Philosophical Investigations is the major work of Ludwig Wittgenstein's later philosophy, published in 1953, two years after his death, in a bilingual German and English edition with a translation by his student G. E. M. Anscombe. It consists of numbered remarks, from a single sentence to a page long, in which Wittgenstein questions, imagines examples, answers an imaginary interlocutor and frequently turns against views he himself had held in the Tractatus Logico-Philosophicus.
Personal Knowledge: Towards a Post-Critical Philosophy was published in 1958 by Routledge and Kegan Paul in London and by the University of Chicago Press. Its author, Michael Polanyi, had been a physician and a distinguished physical chemist before turning to philosophy, and the book grew from his Gifford Lectures at the University of Aberdeen in 1951–52.
Physics and Philosophy: The Revolution in Modern Science is Werner Heisenberg's account of what quantum theory means for our understanding of nature, knowledge and language, set within the history of Western thought from the Greek atomists to the twentieth century. It grew from the Gifford Lectures he gave at the University of St Andrews in the winter of 1955-56 and was published in New York in 1958 by Harper and Brothers in the World Perspectives series, with an introduction by the Yale philosopher F. S. C. Northrop; a German edition, Physik und Philosophie, followed in 1959.
Thomas Kuhn's essay argues that the sciences do not grow by steady accumulation of facts but pass through long periods of settled work broken by revolutions in which the framework of a field is replaced. It was first published in 1962 by the University of Chicago Press as a monograph in the International Encyclopedia of Unified Science, and a second edition of 1970 added a Postscript answering critics.
Philosophy of Natural Science is a short introductory textbook by the German-American philosopher Carl G. Hempel, published in 1966 by Prentice-Hall in its Foundations of Philosophy series. It is still under copyright, so the library holds no text; this record describes the book in its own words and quotes only two short sentences.
Against Method: Outline of an Anarchistic Theory of Knowledge was published in London in 1975 by New Left Books. It began as a long essay of 1970 and was meant to be one half of a joint book with Feyerabend's friend Imre Lakatos, For and Against Method, in which Lakatos would defend scientific rationality and Feyerabend attack it; Lakatos died in 1974, and Feyerabend dedicated the book to him.
The Methodology of Scientific Research Programmes is the first volume of Imre Lakatos's Philosophical Papers, edited after his death by John Worrall and Gregory Currie and published by Cambridge University Press in 1978. It gathers his principal essays in the philosophy of science, written between about 1968 and 1974, around a single idea: the unit of scientific appraisal is not an isolated theory but a research programme, a series of theories that develop over time from a shared core.