set theory
noun
: a branch of mathematics or of symbolic logic that deals with the nature and relations of sets
set theoretic
adjective
Examples of set theory in a Sentence
Recent Examples on the Web
But the resolution to Poincaré’s confusion would come not from geometry, but from a nascent branch of logic called set theory.
—
Konstantin Kakaes, Quanta Magazine, 20 May 2026
Descriptive set theory dates back to Georg Cantor, who proved in 1874 that there are different sizes of infinity.
—Joseph Howlett, Wired News, 4 Jan. 2026
Cantor’s set theory flips the script in a sense.
—Big Think, 25 Nov. 2025
But the viewer doesn’t need to know a thing about set theory to find her organization of lines and angles beautiful.
—Grace Edquist, Vogue, 25 Nov. 2024
Zermelo introduced the axiom of choice because the eight axioms of the Zermelo-Fraenkel set theory were not powerful enough and could not be used to construct a selection function.
—Manon Bischoff, Scientific American, 1 Oct. 2024
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Konstantin Kakaes, Quanta Magazine, 20 May 2026
Descriptive set theory dates back to Georg Cantor, who proved in 1874 that there are different sizes of infinity.
—Joseph Howlett, Wired News, 4 Jan. 2026
Cantor’s set theory flips the script in a sense.
—Big Think, 25 Nov. 2025
But the viewer doesn’t need to know a thing about set theory to find her organization of lines and angles beautiful.
—Grace Edquist, Vogue, 25 Nov. 2024
Zermelo introduced the axiom of choice because the eight axioms of the Zermelo-Fraenkel set theory were not powerful enough and could not be used to construct a selection function.
—Manon Bischoff, Scientific American, 1 Oct. 2024
Cite this Entry
“Set theory.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/set%20theory. Accessed 24 May. 2026.
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