Priori

Part of speech: adjective, adverb

Definitions

  1. A type of reasoning that derives conclusions from existing principles or assumptions | A method of knowledge acquisition that is independent of experience | A philosophical term describing a form of knowledge based on logical deduction rather than empirical observation
  2. A category of reasoning that reaches conclusions based on theoretical premises rather than empirical evidence
  3. A philosophical approach that emphasizes knowledge derived from inherent reasoning rather than sensory experience

Etymology: The term "a priori" is a Latin phrase that entered English usage in the 17th century, carrying a philosophical meaning rooted in reasoning independent of experience. Literally translating as "from the former," it contrasts with "a posteriori," meaning "from the latter" or based on observation. The phrase was adopted directly from Latin scholarly discourse, particularly in the context of logic and epistemology. Tracing back to its Latin roots, "prior" means "former" or "earlier," derived from the comparative form of "prius," which means "before" in both time and order. The addition of "a" functions as a preposition meaning "from," so "a priori" succinctly conveys the idea of knowledge or justification that precedes empirical evidence. Philosophers such as René Descartes and Immanuel Kant popularized these terms to distinguish types of knowledge. Kant, in particular, made a clear distinction between "a priori" knowledge—those truths accessible through reason alone—and "a posteriori" knowledge, which depends on sensory experience. This conceptual framework became central to modern philosophy and shaped scientific inquiry. In English, the term functions as both an adjective and an adverb, used to describe assumptions, arguments, or knowledge derived from theoretical deduction rather than from observation or experimentation. Its precise and technical usage reflects its classical and philosophical heritage, maintaining a formal tone in academic and intellectual contexts.

Synonyms: deductive, theoretical, preconceived, innate, a priori

Antonyms: empirical, posteriori, observational, experiential