Definition of A PRIORI

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A priori, Latin for "from the former", is traditionally contrasted with a posteriori. The term usually describes lines of reasoning or arguments that proceed from the general to the particular, or from causes to effects. Whereas a posteriori knowledge is knowledge based solely on experience or personal observation, a priori knowledge is knowledge that comes from the power of reasoning based on self-evident truths. So, for example, "Every mother has had a child" is an a priori statement, since it shows simple logical reasoning and isn't a statement of fact about a specific case (such as "This woman is the mother of five children") that the speaker knew about from experience.

Examples of a priori in a Sentence

There's no a priori reason to think your expenses will remain the same in a new city. an a priori argument for the defendant's innocence

Recent Examples on the Web In the nascent American Republic, where some humans could vote and most others were in coverture to their voting husbands or were the property of those men, the notion of majority representation was corrupted a priori. — Shannon Pufahl, The New York Review of Books, "Numbering the Dead," 21 Apr. 2020 By the 1970s Richter had also become intrigued with the possibilities of pictures that originated not in a preselected image, but in an a priori set of rules. — Susan Tallman, The New York Review of Books, "The Master of Unknowing," 25 Apr. 2020 But the non-black people at the conference could not comprehend or explain this a priori species division between the human and the slave. — Frank B. Wilderson Iii, Harper's Magazine, "Color Theory," 30 Mar. 2020 But this season, Jamie is very much like Ambrose, and there’s something dark inside them that seems to be a priori — a given, not something that can be explained, or apologized for, or looked at to see if it can be corrected. — Jennifer Vineyard, New York Times, "Bill Pullman Digs Deeper on ‘The Sinner’ Season 3 Finale," 26 Mar. 2020 Our cognitive analysis is not intended to debunk every anti-GMO claim a priori. — Stefaan Blancke, Scientific American, "Why People Oppose GMOs Even Though Science Says They Are Safe," 18 Aug. 2015 For anyone with a truly open mind, the a priori case for UFOs as a scientific anomaly is firmly established. — Kyle Mizokami, Popular Mechanics, "70 Years and Counting, the UFO Phenomenon Is as Mysterious As Ever," 2 July 2018 The look of the films is something that can’t be determined a priori of the rest of its conception. — Ben Sachs, Chicago Reader, "An interview with Lucrecia Martel, Argentina's greatest filmmaker," 16 Apr. 2018 For Kant, reason is universal, infallible and a priori—meaning independent of experience. — Yoram Hazony, WSJ, "The Dark Side of the Enlightenment," 6 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'a priori.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.