set theory

American  

noun

1. the branch of mathematics that deals with relations between sets.

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set theory British  

noun

1. maths the branch of mathematics concerned with the properties and interrelationships of sets

2. logic a theory constructed within first-order logic that yields the mathematical theory of classes, esp one that distinguishes sets from proper classes as a means of avoiding certain paradoxes

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Etymology

Origin of set theory

First recorded in 1940–45

Example Sentences

There are many different ways to construct the disjoint union using the axioms of set theory, which will not produce exactly the same set but will, necessarily, produce isomorphic ones.

From Scientific American • Sep. 14, 2021

Dehn’s concepts of harmonic intervals, topology and set theory entered her work; Ms. Rockburne started thinking of artworks as “visual equations.”

From New York Times • Aug. 8, 2018

Initially, Ms. Rockburne was inspired by set theory, a branch of mathematical logic.

From New York Times • May 4, 2018

Malliaris and Shelah published their proof last year in the Journal of the American Mathematical Society and were honored this past Julywith one of the top prizes in the field of set theory.

From Scientific American • Sep. 16, 2017

Let me tell you, it is hard to care much about set theory when there are twelve trays of brown, light, perfect cream puffs cooling deliciously on a shelf back in your own classroom.

From "The Wednesday Wars" by Gary D. Schmidt