辭彙競爭、不對稱與語法演變： 蒙古語否定結構與時間系統的歷時演變

Lexical Competition, Asymmetries and Diachronic Syntactic Changes: Historical Changes of Negative Constructions and Temporal Systems in Mongolian

本文探討蒙古語兩組否定詞ese/ülü 與ügei 的競爭及其引發的一連串語法演變。從歷時的角度看，蒙古語動詞詞幹前的否定標記ese 和ülü 被動名詞 (verbal noun) 後的ügei（或其虛化的黏著形式 -güi）所取代。我們主張，蒙古語否定標記的位置由動詞之前變為動名詞之後，是不同詞類否定詞彼此競爭的結果，ese 和ülü 是副詞，出現在動詞之前，而ügei 則是存在動詞的否定形式，出現在名詞性詞組之後。兩組否定的功能雖然互補，位置卻不對稱，整個系統尋求對稱的動力促使兩組否定形式彼此競爭。但從語法的共存限制來看，名詞性的靜詞不能以副詞否定，動詞卻可以經過名物化後與否定存在動詞共現，再從認知來看，存在動詞本就可以表示動詞狀態是否存在，ügei 句式便有了先天的優勢，因而勝出。我們還主張，ese/ülü 與ügei(-güi)的競爭結果加速了蒙古語一系列時間語法系統的變化，使蒙古語變得更具分析性。

This paper investigates the competition of two types of negators in Mongolian and a series of syntactic changes in the temporal system it triggered. One type of negative construction is marked by a preverbal negative adverb (ese or ülü) and the other by a postnominal negative head (ügei or its cliticized form -güi). Diachronically, ese and ülü gradually gave way to ügei or -güi. We propose that Mongolian postnominal negators are more robust than the preverbal negators from at least two perspectives. First, a syntactic cooccurance restriction prevents adverbs from modifying and negating a nominal, while a negative EXIST predicate is free from this restriction. Second, EXIST verb is conceptually compatible with verbal states. Finally, we argue that the competition between these two sets of negators triggered and accelerated a series of syntactic changes in the temporal system. As a consequence, Mongolian is becoming more analytic, representing time by converbs/verbal nouns and an omissible present-tense verb of ‘existence’ rather than by a tensed verb.