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

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

This past July, Malliaris and Shelah were awarded the Hausdorff medal, one of the top prizes in set theory.

From Scientific American • Sep. 16, 2017

Most mathematicians had expected that p was less than t, and that a proof of that inequality would be impossible within the framework of set theory.

From Scientific American • Sep. 16, 2017

It would be little comfort to Cantor that his work was the foundation of a whole new branch of mathematics: set theory.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife