Epistemology — Paul Maxwell

Analytic PhilosophyThe 20th-century tradition characterized by formal precision, linguistic clarity, piecemeal problem-solving, and close engagement with logic and the sciences.TraditionsPhilosophy20th Century

AvicennaThe distinction between essence and existence, the argument from contingency to a necessary being, and the Canon of Medicine.FiguresPhilosophyc. 980–1037

Brandolini's lawThe energy needed to refute nonsense is an order of magnitude greater than the energy needed to produce it.ConceptsMind

Charles DarwinExplained the appearance of design without a designer, which reshaped philosophy as much as biology.FiguresPhilosophy1809–1882

Charles Sanders PeirceThe American polymath who founded pragmatism with the 1878 paper How to Make Our Ideas Clear, made fundamental contributions to formal logic and semiotics, and produced one of the most original philosophical bodies of work in the nineteenth century — most of it published only after his death.FiguresPhilosophy19th Century

CogitoDescartes's foundational principle — cogito ergo sum, 'I think, therefore I am' — the indubitable certainty of the thinking subject's existence, recovered through systematic doubt as the foundation of modern philosophy.ConceptsPhilosophyEarly Modern

Coherence Without CertaintyThe epistemic posture of holding beliefs as functionally coherent and provisionally adequate without claiming demonstrative certainty — the alternative to both dogmatic conviction and skeptical paralysis.ConceptsPhilosophyContemporary

Critique of Pure ReasonKant's foundational work of Critical philosophy, demonstrating that the mind contributes structuring conditions (space, time, the categories) to all possible experience, and establishing the limits of theoretical knowledge.BooksPhilosophy

De AnimaAristotle's treatise on the soul as the form of a living body, analyzing the faculties of nutrition, sensation, and intellect across plants, animals, and human beings.BooksPhilosophy

Democracy and EducationDewey's 1916 systematic statement of progressive education theory, treating schools as miniature democratic communities and education as the cultivation of dispositions for inquiry-based participation rather than transmission of fixed content.BooksPhilosophy

Discourse on MethodDescartes's 1637 short methodological work, the first major French-language philosophical treatise, containing the famous cogito argument and the four rules of method.BooksPhilosophy

EmpiricismThe thesis that knowledge derives primarily from sensory experience.ConceptsPhilosophy

EmpiricismThe tradition holding that all genuine knowledge originates in sense experience; the mind starts as a blank slate that experience writes on.TraditionsPhilosophyEarly Modern

EpistemeGreek for knowledge in the strict sense — what is known rather than merely believed.ConceptsPhilosophyCross-Era

EpistemologyThe study of knowledge — what it is, how we get it, and the limits of what can be known.ConceptsPhilosophy

Essay Concerning Human UnderstandingLocke's foundational work of modern empiricism, in four books, arguing against innate ideas and developing the doctrine that all knowledge derives from sensation and reflection.BooksPhilosophy

G. E. MooreThe open question argument and the naturalistic fallacy in ethics; the defence of common sense against scepticism.FiguresPhilosophy1873–1958

George BerkeleyThe Anglo-Irish bishop and philosopher whose subjective idealism — esse est percipi, to be is to be perceived — took empiricism to its most radical conclusion: there are no material substances, only ideas and the minds that perceive them.FiguresPhilosophyEnlightenment

GorgiasSophist and rhetorician who argued that nothing exists, and that if it did, nobody could know or communicate it.FiguresPhilosophyc. 483–375 BC

Hans-Georg GadamerGerman philosopher (1900–2002), Heidegger's student and later interlocutor, whose Wahrheit und Methode (1960) developed philosophical hermeneutics into a comprehensive theory of understanding that grounded twentieth-century reflection on interpretation across philosophy, theology, history, jurisprudence, and the human sciences.FiguresPhilosophy20th Century

Hitchens's razorWhat can be asserted without evidence can be dismissed without evidence.ConceptsMind

How to Make Our Ideas ClearPeirce's 1878 Popular Science Monthly paper containing the founding statement of the pragmatic maxim and the central methodological proposal of the pragmatist tradition.BooksPhilosophy

Immanuel KantThe Königsberg philosopher whose Critical philosophy redrew the map of metaphysics, epistemology, and ethics, and whose work organized nearly all subsequent Continental thought.FiguresPhilosophyEnlightenment

InductionReasoning from observed cases to a general claim or to an unobserved case.ConceptsPhilosophy

Inherited vs. Chosen BeliefThe applied-epistemology distinction between beliefs absorbed pre-reflectively from one's culture and beliefs deliberately taken up after examination, with consequences for how each kind is held, defended, and revised.ConceptsPhilosophyContemporary

John DeweyThe American philosopher who developed pragmatism into a systematic philosophy of inquiry, experience, education, and democracy across more than seventy years of continuous publication — the most institutionally consequential American philosopher of the twentieth century.FiguresPhilosophy20th Century

John LockeThe English philosopher whose Essay Concerning Human Understanding founded modern empiricism and whose Two Treatises of Government provided the philosophical foundation of liberal political theory.FiguresPhilosophyEnlightenment

John Stuart MillThe English philosopher, economist, and reformer whose work on utilitarian ethics, the philosophy of liberty, the logic of inductive reasoning, and the subjection of women shaped Victorian and modern liberal thought.FiguresPhilosophy19th Century

KnowledgeTraditionally defined as justified true belief; problematized by Gettier and beyond.ConceptsPhilosophy

Ludwig WittgensteinThe Austrian-British philosopher whose two distinct phases — the picture theory of the Tractatus (1921) and the language-games of the Philosophical Investigations (1953) — each defined a distinct period of twentieth-century analytic philosophy.FiguresPhilosophy20th Century

Meditations on First PhilosophyDescartes's foundational work of modern philosophy, six meditations developing the method of systematic doubt, the cogito, and the reconstruction of knowledge from indubitable foundations.BooksPhilosophy

Michel de MontaigneInvented the essay, and revived ancient scepticism in a form that set the problem Descartes tried to answer.FiguresPhilosophy1533–1592

Occam's razorThe principle that entities should not be multiplied beyond necessity — where two explanations account equally well for the evidence, prefer the one with fewer commitments.ConceptsPhilosophy

PhenomenologyThe twentieth-century tradition that takes the rigorous description of the structures of conscious experience — not its empirical psychology but its essential structures — as the foundation of philosophy.TraditionsPhilosophy20th Century

Philosophical InvestigationsWittgenstein's posthumous 1953 masterwork developing the account of meaning as use, the analysis of language as practice organized into language-games, and the famous private language argument.BooksPhilosophy

PragmatismJames's 1907 book, from eight public lectures — the most readable statement of pragmatism, and the one whose loose formulation of truth gave its critics everything they needed.BooksPhilosophy

PragmatismThe American tradition holding that the meaning of a concept lies in its practical consequences, and the truth of a belief in its capacity to work — to help us cope, predict, and act.TraditionsPhilosophy20th Century

Problem of InductionHume's argument that inductive inference — from observed cases to unobserved ones — cannot be rationally justified without circularity, and yet underlies most of what counts as empirical knowledge.ConceptsPhilosophyEnlightenment

ProtagorasThe best known of the Sophists, and the source of the claim that man is the measure of all things.FiguresPhilosophyc. 490–420 BC

RationalismThe thesis that reason, not experience, is the primary source of substantive knowledge.ConceptsPhilosophy

RationalismThe early modern tradition (Descartes, Spinoza, Leibniz) holding that substantive knowledge of the world is available through reason alone, independently of experience.TraditionsPhilosophyEarly Modern

René DescartesThe French philosopher and mathematician whose Meditations on First Philosophy and method of systematic doubt founded modern philosophy by relocating its starting point in the certainty of the thinking subject.FiguresPhilosophyEarly Modern

SkepticismThe position that knowledge is unattainable or radically uncertain — from Pyrrho to Descartes' demon.ConceptsPhilosophy

SkepticismThe tradition of suspending judgment where evidence does not settle a question — Pyrrhonism seeking tranquillity through balanced arguments, Academic skepticism arguing that nothing can be known.TraditionsPhilosophyc. 360 BC – present

SophistryFifth-century BC Greek teachers of rhetoric and argument who taught for a fee, and who first argued that law and custom are human conventions rather than natural facts.TraditionsPhilosophy5th–4th century BC

Synthetic A PrioriKant's central epistemological category: knowledge that is both synthetic (extending what is known beyond the analysis of concepts) and a priori (independent of experience for its justification).ConceptsPhilosophyEnlightenment

Tabula RasaThe empiricist doctrine that the human mind at birth contains no innate ideas or principles, originating with Aristotle and given its canonical modern statement by Locke in 1689.ConceptsPhilosophyCross-Era

The Gettier problemA three-page paper from 1963 showing that a belief can be true, and justified, and still obviously not knowledge — because the justification and the truth can come apart by luck.ConceptsPhilosophy

Thomas KuhnArgued that science proceeds by long stable periods punctuated by revolutions that replace the framework itself.FiguresPhilosophy1922–1996

Tractatus Logico-PhilosophicusWittgenstein's 1921 treatise organized as numbered propositions developing the picture theory of meaning and ending with the famous injunction that what cannot be spoken about must be passed over in silence.BooksPhilosophy