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[[FILE:Kleine Welten IX (Small Worlds IX) MET DP855300.jpg|border|right|thumb| [[Arts#:Category:Wassily Kandinsky|Wassily Kandinsky]] - Small Worlds IX <ref>[[Arts#:Category:Wassily Kandinsky|Wassily Kandinsky]] - [https://commons.wikimedia.org/wiki/File:Kleine_Welten_IX_(Small_Worlds_IX)_MET_DP855300.jpg?uselang=en Small Worlds IX], 1922, [https://en.wikipedia.org/wiki/Metropolitan_Museum_of_Art Metropolitan Museum of Art]</ref> ]]

A '''Static Exchange Evaluation (SEE)''' examines the consequence of a series of exchanges on a single [[Squares|square]] after a given [[Moves|move]], and calculates the likely evaluation change ([[Material|material]]) to be lost or gained, [[Donald Michie]] coined the term [[SOMA#SwapoffSwapOff|swap-off value]]. A positive static exchange indicates a "winning" move. For example, PxQ will always be a win, since the Pawn side can choose to stop the exchange after its Pawn is recaptured, and still be ahead. Some programs optimize the SEE function to only return a losing or equal/winning flag, since they only use SEE to determine if a move is worth searching and do not need the actual value. SEE is useful in [[Move Ordering|move ordering]], [[Futility Pruning|futility pruning]] and especially in [[Quiescence Search|quiescence search]] in conjunction with [[Delta Pruning|delta pruning]], as well to [[Reductions|reduce]] "bad" [[Captures|captures]] and [[Check|checks]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=40100 Reducing/Pruning Bad Captures (SEE < 0)] by [[Edsel Apostol]], [[CCC]], August 19, 2011</ref> .

Instead of using a [[Quiescence Search|quiescence search]], some (early) chess programs aimed to determine the material balance of a position by a static analysis of '''all''' possible capture-move sequences. These routines are often referred to as [[SOMA#SOMAALGO|SOMA]] ('''S'''wapping '''O'''ff '''M'''aterial '''A'''nalyzer) <ref>[[Hiroyuki Iida]], [[Makoto Sakuta]], [[Jeff Rollason]] ('''2002'''). ''Computer Shogi''. Artificial Intelligence, Vol. 134, [https://en.wikipedia.org/wiki/Elsevier Elsevier], [http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.130.2727 CiteSeerX]</ref> based on the [[SOMA#SwapoffSwapOff|swap-off algorithm]] used in the one-ply analyzing "paper machine" [[SOMA]] by [https://en.wikipedia.org/wiki/Evolutionary_biologist evolutionary biologist] [[John Maynard Smith]], the '''S'''mith '''O'''ne-'''M'''ove '''A'''nalyzer designed in the early 60s <ref>[[John Maynard Smith]], [[Donald Michie]] ('''1961'''). ''Machines that play games''. [https://en.wikipedia.org/wiki/New_Scientist New Scientist], 12, 367-9. [http://books.google.com/books?id=lo7r0zX_T0sC&lpg=PA369&dq=Machines%20that%20play%20games.%201961%2C%20New%20Scientist%2C%2012&pg=PA367#v=onepage&q&f=false google books]</ref> .

* [https://www.stmintz.com/ccc/index.php?id=161209 SEE and possible EXChess bug] by [[Gian-Carlo Pascutto]], [[CCC]], April 01, 2001 » [[EXchess]] <ref>[https://www.stmintz.com/ccc/index.php?id=162704 EXchess v4.02 released] by [[Dan Daniel Homan]], [[CCC]], April 10, 2001</ref>