log·​ic | \ ˈlä-jik How to pronounce logic (audio) \

Definition of logic

1a(1) : a science that deals with the principles and criteria of validity of inference and demonstration : the science of the formal principles of reasoning a professor of logic
(2) : a branch or variety of logic modal logic Boolean logic
(3) : a branch of semiotics especially : syntactics
(4) : the formal principles of a branch of knowledge the logic of grammar
b(1) : a particular mode of reasoning viewed as valid or faulty She spent a long time explaining the situation, but he failed to see her logic.
(2) : relevance, propriety could not understand the logic of such an action
c : interrelation or sequence of facts or events when seen as inevitable or predictable By the logic of events, anarchy leads to dictatorship.
d : the arrangement of circuit elements (as in a computer) needed for computation also : the circuits themselves
2 : something that forces a decision apart from or in opposition to reason the logic of war

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Other Words from logic

logician \ lō-​ˈji-​shən How to pronounce logician (audio) \ noun

How are logistics and logic related?

Logistics follows the same pattern of other plural nouns—such as ballistics, linguistics, statistics, or physics—that represent fields of study and take either a singular or plural verb.

Logic, used strictly in the singular, is a science that deals with the formal principles of reason. If a visitor walks in the house with wet hair, it is logical for one to assume that it is raining outside. Logistics, which involves such concerns as the delivery of personnel or supplies in an efficient manner, can often employ logic, such as by reasoning out the path least likely to interrupt the flow of a delivery:

As with many other areas of the economy, the digital revolution is having a profound effect on delivery logistics. The combination of mobile computing, analytics, and cloud services, all of which are fueled by the Internet of Things (IoT), is changing how delivery and fulfillment companies are conducting their operations.
—Andrew Meola, Business Insider, 14 Oct. 2016

Both logic and logistics ultimately derive from the Greek logos, meaning "reason." But while logic derives directly from Greek, logistics took a longer route, first passing into French as logistique, meaning "art of calculating," and then into English from there.

Examples of logic in a Sentence

If you just use a little logic, you'll see I'm right. There's no logic in your reasoning. There's some logic to what he says. There's a certain logic in what he says. The revolution proceeded according to its own logic. the logic of the situation
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Recent Examples on the Web But a hyperfocus on the logics that arguably facilitated the success of the missionary’s visual campaign obscures a proper situating of the humanitarian photograph in the white imaginary. Zoé Samudzi, The New Republic, "White Witness and the Contemporary Lynching," 16 May 2020 There’s an obvious economic logic for governments to use this moment to spend boldly to build a clean-energy economy. Justin Worland, Time, "As the Rest of the World Plans a Green Recovery, America Is Once Again Falling Behind," 15 May 2020 Cold commercial logic sent Japanese coffin-makers to Zhuangzhai. The Economist, "Chaguan A small town in China makes half of Japan’s coffins," 14 May 2020 But the episode has unfolded according to a blunt political logic that tracks with trends nationwide. Anchorage Daily News, "In a coronavirus response riven by politics, masks are latest Rorschach test," 12 May 2020 The second strategy proceeds from a different logic. Godfrey Pearlson, Scientific American, "Marijuana May Not Lower Your IQ," 7 May 2020 But converting those instructions to C code that's parsable and easily editable by humans is far from a simple process (and automated tools that convert that assembly code to C often introduce logic errors or obfuscate the code too severely). Kyle Orland, Ars Technica, "Beyond emulation: The massive effort to reverse-engineer N64 source code," 6 May 2020 Bob Waugh, 60, a retired ment law enforcement officer from Lodi who was at the Sacramento protest, said California’s response to the crisis followed no logic. Alexei Koseff, SFChronicle.com, "Protesters in Sacramento and San Francisco defy shelter-in-place order to demand California reopen," 1 May 2020 The same logic applies to all other aspects of using your cup, from dumping fluid to cleaning and reinserting it. Patia Braithwaite, SELF, "If You’ve Been Curious About Menstrual Cups, Now’s the Time to Try," 30 Apr. 2020

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

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First Known Use of logic

12th century, in the meaning defined at sense 1a(1)

History and Etymology for logic

Middle English logik, from Anglo-French, from Latin logica, from Greek logikē, from feminine of logikos of reason, from logos reason — more at legend

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Time Traveler for logic

Time Traveler

The first known use of logic was in the 12th century

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Statistics for logic

Last Updated

23 May 2020

Cite this Entry

“Logic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/logic. Accessed 31 May. 2020.

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More Definitions for logic


How to pronounce logic (audio)

English Language Learners Definition of logic

: a proper or reasonable way of thinking about or understanding something
: a particular way of thinking about something
: the science that studies the formal processes used in thinking and reasoning


log·​ic | \ ˈlä-jik How to pronounce logic (audio) \

Kids Definition of logic

1 : a proper or reasonable way of thinking about something : sound reasoning There's no logic in what you said.
2 : a science that deals with the rules and processes used in sound thinking and reasoning

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