對印度教吠檀多不二論的宗師商羯羅（Śaṅkara）而言，作為萬有本體以及吾人真性的大梵或真我（梵我，brahman-ātman），不具有任何屬性，也超越一切思想與言詮，易言之，梵我是非語言思議所能臻及的“不可說者”。問題是，以語言指涉終極真實一事似手無可避免，此外，商氏推崇的《奧義書》等聖典也於梵我多所言說。如是，對商羯羅而言，我人應如何理解聖典語言的指涉作用？我人還能否以任何方式言說那不可說者？在簡略介紹商羯羅的不二論哲學之後，本文探討《奧義書》與商羯羅本人以梵我不可言詮的理由。其次，我們依序論述商氏所採取，語言之於不可說者的三種表示法，亦即：（1）訴諸否定語的遮撥法。（2）訴諸間接肯定語辭的指示法。（3）訴諸明言的增益及其否定的隨說隨掃法。其後，本文參就「增益及其否定」一概念，討論這三種表示法的異同關係。我們認為，商羯羅對於「如何言說不可說者」一課題所提出的語言哲學進路頗其深意，也有極大的參考價值。
For Śaṅkara, the most renowned teacher of the Advaita Vedānta school of Hinduism, Brahman or Ātman as the sole ultimate reality underlying all beings is attribute-less, indivisible, unconceptualizable and unverbalizable. In other words, Brahman-Ātman is for him ineffable, well beyond the reach of human language. Yet, referring to the reality in words seems on many occasions inevitable, and the scriptures of the school do contain positive statements about the reality. How, then, should we understand the referring function of the scriptural language? How can one speak meaningfully of something that is unspeakable? In this paper I propose to expound Śaṅkara's views on these issues.Śaṅkara, indeed, sets forth three methods by means of which one can make linguistic references to the unsayable: (1) the method of negation (netivāda), (2) the method of indication (laksanā-vrtti), and (3) the method of imposition-cum-negation (adhyāropa-apavāda). The three methods will be closely examined in sequence with their mutual relationships exposed thereafter. The author is of the opinion that Śaṅkara's linguistic approach toward 'saying' the unsayable is rather instructive and really worth our attention.
