|
Zugzwang (German for "compulsion to move", ) is a situation found in chess and other games wherein one player is put at a disadvantage because they must make a move when they would prefer to pass and not move. The fact that the player is compelled to move means that their position will become significantly weaker. A player is said to be "in zugzwang" when any possible move will worsen their position. The term is also used in combinatorial game theory, where it means that it directly changes the outcome of the game from a win to a loss, but the term is used less precisely in games such as chess. Putting the opponent in zugzwang is a common way to help the superior side win a game, and in some cases, it is necessary in order to make the win possible. The term "zugzwang" was used in German chess literature in 1858 or earlier,〔 and the first known use of the term in English was by World Champion Emanuel Lasker in 1905.〔 The concept of zugzwang was known to players many centuries before the term was coined, appearing in an endgame study published in 1604 by Alessandro Salvio, one of the first writers on the game, and in shatranj studies dating back to the early 9th century, over 1000 years before the first known use of the term. Positions with zugzwang occur fairly often in chess endgames. According to John Nunn, positions of reciprocal zugzwang are surprisingly important in the analysis of endgames.〔 ==Etymology== The word comes from German ''Zug'' "move" + ''Zwang'' "compulsion". According to chess historian Edward Winter, the term had been in use in German in the 19th century. Pages 353–358 of the September 1858 Deutsche Schachzeitung had an unsigned article 'Zugzwang, Zugwahl und Privilegien'. F. Amelung employed the terms Zugzwang, Tempozwang and Tempozugzwang on pages 257–259 of the September 1896 issue of the same magazine. When a perceived example of zugzwang occurred in the third game of the 1896–97 world championship match between Steinitz and Lasker, after 34...Rg8, the Deutsche Schachzeitung (December 1896, page 368) reported that 'White has died of zugzwang'. The earliest known use of the term "zugzwang" in English was on page 166 of the February 1905 issue of ''Lasker's Chess Magazine''. The term did not become common in English-language chess sources until the 1930s, after the publication of the English translation of Nimzowitsch's ''My System'' in 1929.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Zugzwang」の詳細全文を読む スポンサード リンク
|