Occam's razor

American  

noun

1. the maxim that assumptions introduced to explain a thing must not be multiplied beyond necessity.

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Occam's razor British  

noun

1. a variant spelling of Ockham's razor

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Occam's razor Scientific  

/ ŏk′əmz /

1. A rule in science and philosophy stating that entities should not be multiplied needlessly. This rule is interpreted to mean that the simplest of two or more competing theories is preferable and that an explanation for unknown phenomena should first be attempted in terms of what is already known. Occam's razor is named after the deviser of the rule, English philosopher and theologian William of Ockham (1285?–1349?).

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Etymology

Origin of Occam's razor

First recorded in 1900–05; after William of Occam

Example Sentences

While Endres acknowledges the idea as logically possible, he notes that it runs counter to Occam's razor, the principle that favors simpler explanations.

From Science Daily • Oct. 26, 2025

Asked what he would have done different four years ago, Baffert offered an Occam’s razor kind of answer.

From Los Angeles Times • Apr. 30, 2025

Doctors often invoke the principle of Occam’s razor, articulated by the 14th-century philosopher William of Occam, who posited that the simplest interpretation of any phenomenon is most likely the right one.

From New York Times • May 26, 2022

I am a great believer in the principle of Occam's razor.

From Salon • Jul. 13, 2020

It seems better to employ the principle of economy known as Occam’s razor and cut out all the features of the theory that cannot be observed.

From "A Brief History of Time: And Other Essays" by Stephen Hawking