本文指出，在高達美的詮釋學，語言一方面處於人與事理、人與他人的中間，另方面具有傳遞訊息的功能。籍著這兩種性格，語言統一了人與事理、人與他人，甚至讓他們各自成為其自己。我首先從對話中指出語言的本性，再從三方面說明語言的統一能力。它們是：1.語詞本身的性格，2.語詞作為光輝，和3.語詞的玄照性。在結論中，我指出，語言的統一能力使它成為宇宙的存有學基礎。

　　　　　In this essay, I argue that on Gadamer's hermeneutics language has, in addition to serving as a medium of communication, a twofold function, i.e., to unify an individual with the world so as to form a Being-in-the-world and to unify an individual with others so as to form a community. I call this function the unifying power of language. I shall firstly characterize the nature of language by virtue of the structure of dialogue. I then justify the unifying power of language from three distinct approaches, namely, (i)the nature of word, (ii)word as light, (iii)the speculative structure of word. On the basis of this analysis, we may claim, as a conclusion, that the unifying power of language will pave a solid foundation to an ontology of the whole universe.