This paper attempts to clarify the interdependence between usage of language and soteriological conception in Tiantai Buddhism. Closely associated with this issue is the question of the limits of verbal expression raised by speculative reflections on language in this Buddhist school. According to the Tiantai Buddhist vision of soteriology, the limit between the expressible and the inexpressible could be described as the turning point from intentional usage of language into its pragmatic mode.
Intentional usage of language includes that kind of verbal articulation, which expresses cognitional and volitional contents of consciousness. Pragmatic usage of language refers to verbal articulation, which functions as means of expediency within a soteriological context. Tiantai Buddhism regards verbal meanings construed by intentional usage of language as ultimately unreal, and all entities identified with these meanings are considered as illusory. Existing things are believed to be devoid of any substantial reality of itself; but recognized as discrete entities corresponding to verbal meanings, their original non-abidingness is inverted into an abiding substance, which is regarded as illusory. However, this illusory state of inversion caused through intentional usage of language includes an instructional value, because it inversely refers back to what is real. The pragmatic relevance of this instructional value is signified, then, as provisional mode in verbal articulation. Pragmatic usage of language emphasizes the provisional character of verbal meaning by means of paradoxical articulation. As soon as some soteriological meaning is verbalized, it must be denied, to signify its provisional character. Pragmatic usage of language maintains its reference to the soteriological meaning of “non-attachment” by means of paradoxical articulation. It constructs and simultaneously restricts meanings to its provisional significance through the deconstructive function of paradoxical articulation. Intentional usage turns then into pragmatic usage of language, and the latter is supposed to be capable of embodying the Buddha-dharma’s ultimate meaning. Consequently, the difference between the two modes of using language consists of a difference between the attitudes of “attachment” and “non-attachment” to verbal meanings.
In Tiantai Buddhism the verbalized represents the illusive realm; the inexpressible represents ultimate reality. On the other hand, ultimate reality cannot but be manifested through this inverse mode of illusory meaning in verbal articulation; and the illusory realm cannot but be based on ultimate reality. As soon as one of the two is taken into account, the other cannot be neglected either. If the inexpressible were completely devoid of any reference to linguistic articulation, it would be finally meaningless, which entails nihilism; even its soteriological meaning would be baseless. Conversely, the verbalized inversely hints at what is ultimately real – the inexpressible. Essentially, the verbalized is then the inexpressible in its mode of illusive inversion. Tiantai Buddhist soteriology claims paradoxical identity of ultimate reality and its mode of illusion. Ultimate reality devoid of its inversion into illusion would be nothingness. Its inversion into illusion is a necessary device of manifesting its soteriological value. Soteriology of Tiantai Buddhism essentially relies on the viewpoint that the sacred and profane exclusively refer to each other. The illusory moment of the profane manifests the significance of the sacred by means of “instructional inversion.” Consequently, the soteriological doctrine of “non-duality between the sacred and profane” is closely related with the issue of the expressible and inexpressible in Tiantai Buddhism. Tiantai Buddhism expresses its dialectics between the verbalized and inexpressible corresponding to the “non-duality between the sacred and profane” through the doctrine of “threefold truth”. In this paper I will display the interdependence between the inexpressible and verbalized according to the Tiantai viewpoint of “threefold truth”.
本文旨在，分析出與天台宗之救度學義相關的語言用法，以及天台宗對語言界限上的觀點。天台宗將「度一切眾生」視為其救度學理想；就其理論性的根據而言，天台宗不得不預設「聖凡不二」之教義。智顗認為，基於此一教義才能顯示出，天台宗「轉識成智」的教化方式所以完整「度一切眾生」的理想。但是依大乘佛教而觀，佛法之聖賢義為不可說，所以一切文字表達只能代表一種世俗義。
筆者認為，依天台宗而言，世俗義之「可說」與聖賢義之「不可說」兩個領域之間的界線可以被理解為「意向性的語言用法」與「實用性的語言用法」之間的轉變點。意向性的語言用法指是，語言表達在一切意識活動的認識以及意志趨向上所指涉的名義；實用性的語言用法則指的是，語言表達在佛法救度的功夫上的手段義。天台宗認為前者所成立者為虛假，但是它含有其價值引導；在其暫時性的形態中，意向性的語言用法發揮文字表達的實用涵義。後者依其暫時性之實用涵義來展現佛法之終極意義。因此兩種語言用法之差別在于一種「執著」及「無執著」之不同。「可說」之詞義關涉到一種既虛假也限定的對象界，「不可說」體現為一種多重涵義的終極實在本身；然而終極實在不得不倒映於與其相反的虛假形態而呈現，而虛假的領域仍須依于一終極實在的根源；是故舉其一端必具另外一端，是故「可說」與「不可說」之間，乃是實在與虛假之「敵對相即」或「同體不異」。
因為如此，天台宗並不將「可說」與「不可說」構思為兩種彼此排斥的領域；依天台宗的辯證法而言，世俗性之「可說」與聖賢義之「不可說」雖互為對立，其卻交互指涉。因此其交互指涉亦對應到天台宗「聖凡不二」的救度依據。天台宗借用「三諦」的中國佛學術語來展現其語言哲學義。本文專就與天台宗「三諦」觀相關聯的語言哲學義加以探討。

華嚴宗判佛教為小始終頓圓五教，三祖法藏(643-712)將頓教說為離言真如，頓教乃作為由可說之小始終教跨向圓教之時，所特別標舉出之不可說的特性。然其可說與不可說之關係略分可分為兩重︰一是頓教之可說與不可說﹔一為圓教之可說與不可說。頓教與圓教對此問題有不同的說法，但皆主張可說與不可說是不一不二，亦即可說與不可說彼此是圓融無礙。
若依同時也是禪宗荷澤系法裔之華嚴四祖澄觀(738-839)五祖宗密(780-841)，則認為頓教等同禪宗，華嚴思想與禪宗之關連性，日人鎌田茂雄編有《禪典籍內華嚴資料集成》(1984東京：大藏出版社)一書已可資證明，禪宗倡教外別傳直指心性，參究公案遂為開悟之重要方法，然禪宗公案之「可說與不可說」推其原始，應與華嚴頓教有其相關。
華嚴與天台思想代表中印佛學融合後的兩種不同的型態，但共同以「圓教」為最終極的教法，其中有差異也有相同之處。歷來天台與華嚴之間即不斷相互吸收、相互批判，其對話傳統已逾千年。然二者就其作為教導眾生證悟絕對真實的法門此一本質來說，其必然面對可說之教法與不可說真實之間的弔詭，因此對語言限度的思考，便為其哲學理論建構的必要課題，而再加入維根斯坦對語言界限的反省，形成天台華嚴與維根斯坦三者之間的多重對話，對於華嚴宗哲學之研究可以開發一種全新的方向，也可以令人重新思考天台與華嚴哲學的差別。
Huayen Buddhism classifies Buddhist doctrines according to five types of teaching: the small teaching, the initial teaching, the final teaching, the sudden teaching and the perfect teaching. The third patriarch Fazang(643-712) explains the sudden teaching as true suchness beyond words. The sudden teaching is marked by the inexpressible; it combines the small, initial and final teaching with perfect teaching. However, the interrelation of the expressible and inexpressible can be distinguished in two ways: the sudden teaching type and perfect teaching type. Both of them regard the relationship between the expressible and inexpressible as ‘non-identity and non-duality’, it means that expressible and inexpressible can not obstruct each other, but cohere with each other.
The fourth and fifth Huayen patriarchs who simultaneously were Chan disciples held that the sudden teaching is nothing but Chan-school. The Japanese scholar Kamadashigeo proves the relationship between Huayen and Chan Buddhism in his work The Collection of Huayen-materials in the Chan-canon (Tokyo 1984 Taishou). The Chan-school promulgated the idea of transmission beyond teaching directly from mind to mind. It employed the methods of Gongan to initiate enlightenment. Originally the expressible and inexpressible of the Gongan in Chan-school is related with the sudden teaching in Huayan-school.
Huayen and Tiantai Buddhism represent two types of cultural integration between India and China. Their ultimate level of teaching is identically called ‘perfect teaching’, but except this commonality there are some differences. Historically, there was a lot of mutual influence, exchange and critics between these two schools, in total their dialogue has been lasting for more than thousand years. Both of them must face the paradox of the expressible teaching-level and inexpressible truth, when they instruct sentient beings to experience ultimate truth. For that reason, their thoughts about limits of language become a necessary concern of their philosophy and theoretical speculations. If Wittgenstein’s standpoint about limits of language is taken into account, a complex dialogue between the three standpoints of Tiantai, Huayen and Wittgenstein can be developed and possibly a new tendency in Huayen studies might be explored, which might also be fruitful for shedding light on differences between Huayen and Tiantai.

在當代西方哲學的「語言學轉向」中，維根斯坦是一個主要的代表人物，本文主要針對他（早期的著作中）的語言哲學觀點，特別是他對語言界限的看法進行研究。而作為一個整合型的研究（東西哲學的對話：語言的界限），本文也試圖為「可說與不可說」的問題積極地尋求解答。
本文一開始要先回答為什麼討論「可說與不可說」這個問題有其必要性，並試圖論證如果維根斯坦所做的一切是屬於哲學工作的話，那麼對他來說，解釋什麼是可說的以及什麼是不可說但卻可被顯示的，將是哲學工作中的核心問題。
進一步，我將建構維根斯坦哲學中為「世界、思想、和語言」之間所設立的三重連結組織〈而非一般所謂的「世界與語言」之間的二重連結而已〉，並尋求它們之間的共同結構；我將解釋為什麼「邏輯實在論」會是維根斯坦所能接受的必然結果，而「可能世界」這個觀念將是理解「邏輯實在論」的重要切入點。也就是這個存有學的主張，我們才能說明世界中的原子事實、思想中的邏輯圖像、與語言中的基本語句之間的共同邏輯形式。
建基於邏輯形式之上，我們便能為「可說與不可說」之間的區別〈同時也能為「可想與不可想」之間的區別〉立下一個判準，這個判準十分類似於後來邏輯實證論者所主張之經驗意義的可檢證原則，或者我們可以說可檢證原則其實源自於維根斯坦的「可說與不可說之判準」。
最後，我還要澄清並非一切不可說者皆可被顯示，只有一些有限範圍內的不可說者才能被顯示，例如語言的界限、語言的形式或邏輯特徵、事實和語句間的共同邏輯形式、實在界的邏輯形式、事物的存在、以及世界的存在等。我還要強調所謂不可說但可被顯示者必須在可說之中被顯示（其中邏輯恆真句是一部份特殊的例子，因為雖然他們是可說的，但卻沒說什麼）。而對於不可說也不可顯示者，我們必須保持沉默。