Editing Ramsey theory (section)

{{Short description|Branch of mathematical combinatorics}}
{{for|Ramsey theory of infinite sets|Infinitary combinatorics}}
'''Ramsey theory''', named after the British mathematician and philosopher [[Frank P. Ramsey]], is a branch of the mathematical field of [[combinatorics]] that focuses on the appearance of order in a substructure given a structure of a known size. Problems in Ramsey theory typically ask a question of the form: "how big must some structure be to guarantee that a particular property holds?"<ref>{{cite book| last1 = Graham | first1 = Ron | last2 = Butler | first2 = Steve | title = Rudiments of Ramsey Theory | edition = 2nd  | year = 2015 | publisher = American Mathematical Society | isbn = 978-0-8218-4156-3 | page = 1 |author-link2=Steve Butler (mathematician)}}</ref>