[Revised entry by Laurence R. Horn on June 3, 2024.
Changes to: Main text, Bibliography, notes.html]
This entry outlines the role of the Law of Non-Contradiction (LNC), or Principle of Non-Contradiction (PNC), as the foremost among the first (indemonstrable) principles of Aristotelian philosophy and its heirs, and depicts the relation between LNC and LEM (the law of excluded middle) in establishing the nature of contradictory and contrary opposition. s1 presents the classical treatment of LNC as an axiom in Aristotle’s “First Philosophy” and reviews the status of contradictory and contrary opposition as schematized on…

Originally appeared on Stanford Encyclopedia of Philosophy Read More