Ramsey theory

noun

A branch of mathematics which deals with patterns that inevitably arise in sufficiently large sets (i.e., subsets of some structure).

Meanings

nounRamsey theory (uncountable)
  1. uncountablemathematicsA branch of mathematics which deals with patterns that inevitably arise in sufficiently large sets (i.e., subsets of some structure).

    Ramsey theory can be loosely described as the study of structure which is preserved under finite decomposition.

    1987, R. L. Graham, V. Rôdl, “Numbers in Ramsey Theory”, in C. Whitehead, editor, Surveys in Combinatorics 1987: Invited Papers for the Eleventh British Combinatorial Conference, Cambridge University Press, page 111
    2 more examples

    1999, Randall McCutcheon, Elemental Methods in Ergodic Ramsey Theory, Springer, Lecture Notes in Mathematics: 1722, page 8, We are now ready to offer a loose definition of Ramsey theory. Ramsey theory is a collection of results which, given a finite coloring of some structure, guarantee the existence of certain monochromatic configurations or substructures.

    In the 35 years since the lectures which form this book were given the area of Ramsey theory has continued to undergo tremendous growth, particularly in the last decade.

    2015, Ron Graham, Steve Butler, Rudiments of Ramsey Theory, 2nd edition, American Mathematical Society, page vii

Origin

Named after British mathematician and philosopher Frank P. Ramsey.

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APA

Ramsey theory. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/Ramsey%20theory

MLA

“Ramsey theory.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Ramsey%20theory. Accessed November 4, 2026.

Chicago

WatkinsX Dictionary, s.v. “Ramsey theory,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/Ramsey%20theory.

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