A systematic assault on the claims of every branch of human knowledge. Across eleven books, Sextus Empiricus attacks the foundations of grammar, rhetoric, geometry, arithmetic, astrology, music, logic, physics, and ethics — arguing that none of them can establish certain knowledge.
Start ReadingAgainst the grammarians. Sextus attacks the foundations of grammar as a systematic discipline, questioning whether grammatical rules represent genuine knowledge.
Against the rhetoricians. Sextus argues that rhetoric is not a genuine art, examining and demolishing the claims of rhetorical theory to produce reliable persuasion.
Against the geometers. Sextus attacks the foundations of geometry, challenging the reality of points, lines, and surfaces and the certainty of geometric proofs.
Against the arithmeticians. Sextus argues that number has no real existence, attacking the Pythagorean and Platonic accounts of mathematical reality.
Against the astrologers. Sextus demolishes the claims of astrology, arguing that the positions of celestial bodies cannot determine human affairs.
Against the musicians. Sextus examines and rejects the claim that music theory constitutes genuine knowledge, questioning whether musical harmony has objective reality.
Against the logicians (Book 1). Sextus attacks the criterion of truth — the foundation of all knowledge claims — arguing that no reliable standard exists for distinguishing truth from falsehood.
Against the logicians (Book 2). Sextus continues his attack on logic, examining sign-inference, demonstration, and the Stoic theory of the proposition, and finding each inadequate.
Against the physicists (Book 1). Sextus attacks the fundamental concepts of natural philosophy — body, cause, motion, place, and time — arguing that none can be coherently defined.
Against the physicists (Book 2). Sextus examines and rejects the claims of theology and physics about God, causation, and the nature of the universe.
Against the ethicists. Sextus attacks moral philosophy, arguing that no objective good or evil can be established and that ethical knowledge is as unattainable as any other kind.