a priori
ay pry-OR-eye
/ˌeɪ praɪˈɔːraɪ/
Relating to knowledge that proceeds from theoretical deduction rather than sensory observation.
Independent of physical experience; knowable through pure reason alone.
The story behind the word. Latin for 'from what comes before'. Scholastic thinkers used it for reasoning from cause to effect; Kant later transformed it to mean knowledge independent of sensory experience.
Word relationships
- deductive: Deductive describes the logical mechanism, whereas a priori describes knowledge independent of experience.
- a posteriori: A posteriori knowledge depends directly on observational or empirical evidence.
Commonly confused with
- prior: Prior simply means earlier in time, whereas a priori means prior to sensory experience.
Collocations
- a priori knowledge
- a priori reasoning
- a priori truth
Example sentences
- "The mathematical truth that all triangles have three sides is known a priori." Epistemology
Memory hook
A PRIORI = PRIOR to looking at sensory facts. Known before looking.
When not to use
Do not use in casual speech to mean a personal bias or premature judgment.
Fun facts
- Immanuel Kant reshaped modern thought by asking whether 'synthetic a priori' truths—knowledge both informative and independent of experience—actually exist.
Related words
Also appears in
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