上古漢語中第一人稱「吾」、「我」二字使用存在差異,這種現象早已被人們認識並加以研究。本文著眼于語音系統的特點,發現上古漢語在實現普通重音、局部焦點重音時,均選擇讓第一人稱代詞「我」進入重音位置,而不會選擇「吾」。這不僅為探尋「吾」、「我」對立的真正原因提供了更多、更為有利的證據,而且能夠證明古漢語第一人稱代詞「吾」、「我」換用的原因正是韻素輕重區別。這些新材料支持了上古韻素敏感的語音系統的理論和假說,同時支持了漢語韻律系統轉變的觀點,進一步論證了單音節音步是如何在上古漢語韻律系統中發揮功能的,同時也為漢語語音史的討論開闢了一個嶄新的領域。
The difference between two first-person pronouns 'wu' (吾) and 'wo' (我) in archaic Chinese has been extensively discussed. This paper re-explores this issue from a perspective of prosodic phonology, which reveals that 'wo' can carry stress in a sentence while 'wu' cannot since their respective prosodic forms draw a clear distinction between one another. 'Wo', which is a strong form consisting of more than one morae, contrasts 'wu', the one-mora weaker one. A set of evidence is provided to support this prosodical explanation, as well as to validate the hypothesis of 'Weight-sensitive System' in archaic Chinese. It is also argued that aside from its significant role in the prosodic system, monomoraic syllable foot could change greatly the appearance of the language.