descending wedge

{{Short description|Logic symbol resembling a "V"}}

The descending wedge symbol ∨ may represent:

• Logical disjunction in propositional logic
• Join in lattice theory
• The wedge sum in topology
• The V sign, a symbol representing peace among other things

The vertically reflected symbol, ∧, is a wedge, and often denotes a related or dual operator.

The ∨ symbol was introduced by Russell and Whitehead in Principia Mathematica, where they called it the Logical Sum or Disjunctive Function.{{Cite book |last=Whitehead |first=Alfred North |url=http://name.umdl.umich.edu/aat3201.0001.001 |title=Principia mathematica, by Alfred North Whitehead ... and Bertrand Russell. |date=2005}}

In Unicode the symbol is encoded {{unichar|2228|Logical or|html=}}. In TeX, it is \vee or \lor.

One motivation and the most probable explanation for the choice of the symbol ∨ is the latin word "vel" meaning "or" in the inclusive sense. Several authors use "vel" as name of the "or" function.{{Cite book |last=Rueff |first=Marcel |url=https://books.google.com/books?id=1dJXAAAAYAAJ&q=vel |title=Sets and Boolean Algebra |last2=Jeger |first2=Max |date=1970 |publisher=American Elsevier Publishing Company |isbn=978-0-444-19751-1 |language=en}}{{Cite book |last=Trappl |first=Robert |url=https://books.google.com/books?id=fG1QAAAAMAAJ&q=vel |title=Progress in Cybernetics and Systems Research |date=1975 |publisher=Hemisphere Publishing Corporation |isbn=978-0-89116-240-7 |language=en}}{{Cite book |last=Constable |first=Robert L. |url=https://books.google.com/books?id=YQQnAAAAMAAJ&q=vel |title=Implementing Mathematics with the Nuprl Proof Development System |date=1986 |publisher=Prentice-Hall |isbn=978-0-13-451832-9 |language=en}}{{Cite book |last=Malatesta |first=Michele |url=https://books.google.com/books?id=j0TZo9ZqOxwC&pg=PA85 |title=The Primary Logic: Instruments for a Dialogue Between the Two Cultures |date=1997 |publisher=Gracewing Publishing |isbn=978-0-85244-499-3 |language=en}}{{Cite book |last=Harris |first=John W. |url=https://books.google.com/books?id=DnKLkOb_YfIC&q=vel |title=Handbook of Mathematics and Computational Science |last2=Stöcker |first2=Horst |date=1998-07-23 |publisher=Springer Science & Business Media |isbn=978-0-387-94746-4 |language=en}}

{{Cite book |last=Tidman |first=Paul |url=https://books.google.com/books?id=AxoqAQAAMAAJ&q=vel |title=Logic and Philosophy: A Modern Introduction |last2=Kahane |first2=Howard |date=2003 |publisher=Wadsworth/Thomson Learning |isbn=978-0-534-56172-7 |language=en}}

{{Cite book |last=Kudryavtsev |first=Valery B. |url=https://books.google.com/books?id=K68D8CK9hucC&pg=PA81 |title=Structural Theory of Automata, Semigroups, and Universal Algebra: Proceedings of the NATO Advanced Study Institute on Structural Theory of Automata, Semigroups and Universal Algebra, Montreal, Quebec, Canada, 7-18 July 2003 |last2=Rosenberg |first2=Ivo G. |date=2006-01-18 |publisher=Springer Science & Business Media |isbn=978-1-4020-3817-4 |language=en}}{{Cite book |last=Denecke |first=Klaus |url=https://books.google.com/books?id=NgTAzhC8jVAC&pg=PA193 |title=Universal Algebra and Coalgebra |last2=Wismath |first2=Shelly L. |date=2009 |publisher=World Scientific |isbn=978-981-283-745-5 |language=en}}