# set theory

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

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## Origin of set theory^{}

First recorded in 1940–45

Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

## set theory

- maths the branch of mathematics concerned with the properties and interrelationships of sets
- 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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Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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