first principle

American  

noun

1. any axiom, law, or abstraction assumed and regarded as representing the highest possible degree of generalization.

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first principle British  

noun

1. one of the fundamental assumptions on which a particular theory or procedure is thought to be based

2. an axiom of a mathematical or scientific theory

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Example Sentences

See Examples For:

first principle

As in medicine, the first principle of policymakers is “do no harm.”

From Barron's ● Apr. 30, 2026

The first principle of economics is: Don’t transfer income by distorting prices.

From The Wall Street Journal ● Mar. 31, 2026

"We hope this ban is only the start of a reckoning between society and the tech companies that built these platforms with growth as their first principle instead of safety."

From BBC ● Dec. 11, 2025

The first principle is that the president normally should not be using the military to engage in domestic law enforcement.

From Slate ● Sep. 3, 2025

The first principle of wrestling is to hang on to your opponent come what may, so I clung to Nick's breeches like a leech, though he kicked madly and pummeled my back with his fists.

From "The Shakespeare Stealer" by Gary L. Blackwood