a priori

adjective

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
1
a
b
: relating to or derived by reasoning from self-evident propositions compare a posteriori
c
: presupposed by experience
2
a
: being without examination or analysis : presumptive
b
: formed or conceived beforehand
a priori adverb
apriority
ˌä-prē-ˈȯr-ə-tē
ˌa-;
ˌā-(ˌ)prī-ˈȯr- How to pronounce a priori (audio)
-ˌprē-ˈȯr
noun

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A priori and a posteriori are terms that are used especially in logic and philosophy. A priori is from Latin ā priōrī, which means literally, "from what is earlier." A priori knowledge is knowledge that comes from the power of reasoning based on self-evident truths; a priori usually describes lines of reasoning or arguments that proceed from the general to the particular, or from causes to effects. A posteriori is from Latin ā posteriōrī, which means literally, "from what is later." It describes knowledge based solely on experience or personal observation. So, for example, "Every apple is a fruit" is an a priori statement, since it shows simple logical reasoning and isn't a statement of fact about a specific case; "apples are sweet" is a posteriori, as it expresses something the speaker knows 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
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Knowing a priori which stocks will outperform the market is also much more difficult than reviewing the trends that occurred in the past. Wayne Winegarden, Forbes, 2 Oct. 2024 Alongside this effort, wildlife trafficking should be designated as a predicate offense for wiretap authorizations, which would empower authorities to start gathering intelligence without having to prove a link to other crimes a priori. Vanda Felbab-Brown, Foreign Affairs, 15 May 2023 Given Russia’s indiscriminate shelling and targeting, no type of conventional weapon should be excluded a priori. Petr Fiala, Foreign Affairs, 24 Apr. 2023 And this abstractness of Mr. Wilson is part of a curiously a priori metaphysical idealism. Dan McLaughlin, National Review, 6 Feb. 2024 See all Example Sentences for a priori 

Word History

Etymology

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

First Known Use

1652, in the meaning defined at sense 1a

Time Traveler
The first known use of a priori was in 1652

Dictionary Entries Near a priori

Cite this Entry

“A priori.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/a%20priori. Accessed 22 Nov. 2024.

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