a priori

a pri·​o·​ri | \ ˌä-prē-ˈȯr-ē How to pronounce a priori (audio) , ˌa-; ˌā-(ˌ)prī-ˈȯr-ˌī How to pronounce a priori (audio) , -ˌprē-ˈȯr-ē \

Definition of a priori

1a : deductive
b : relating to or derived by reasoning from self-evident propositions — compare a posteriori
c : presupposed by experience
2a : being without examination or analysis : presumptive
b : formed or conceived beforehand

Other Words from a priori

a priori adverb
apriority \ ˌä-​prē-​ˈȯr-​ə-​tē , ˌa-​ ; ˌā-​(ˌ)prī-​ˈȯr-​ How to pronounce a priori (audio) , -​ˌprē-​ˈȯr \ noun

Synonyms & Antonyms for 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 Until Trump came along, it was accepted a priori that the U.S. had a special duty to maintain the global order for the benefit of everyone. Tom Mctague, The Atlantic, 4 July 2022 The problem is a priori identifying that one small zone, which has proved notoriously difficult to do, even with the most sophisticated, high resolution models. Jason Samenow, Washington Post, 11 Sep. 2020 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, 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, 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, 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, 26 Mar. 2020 Our cognitive analysis is not intended to debunk every anti-GMO claim a priori. Stefaan Blancke, Scientific American, 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, 2 July 2018 See More

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.

First Known Use of a priori

1652, in the meaning defined at sense 1a

History and Etymology for a priori

borrowed from Medieval Latin ā priōrī literally, "from what is earlier"

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The first known use of a priori was in 1652

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Cite this Entry

“A priori.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/a%20priori. Accessed 24 Sep. 2022.

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