人们一般认为，“言为心声”，即有何种思想感情便有怎样的语言表达。然而，语言在许多情况下，又是有限的，不能尽如人意。
It is said "words are the voice of the mind", that is to say whatever thinking and emotions one may have will finally be reflected in his or her language. However, in many cases, language is limited and may not be as powerful as one may expect.
在我国古典文学作品中，不乏这样的表述。例如，刘禹锡的《视刀环歌》：“常恨言语浅，不如人意深”；黄庭坚的《品令》：“口不能言，心下快活自省”；《妙法莲华经·方便品》：“止、止不须说！我法妙难思”，以及“余欲无言”、“解人难索”、“辞不达意”等等。
Concerning the issue, there is no shortage of descriptions of this kind in Chinese classical literatures. For examples, Liu Yuxi (772–842) wrote: "How lamentable it is that words are so powerless to express one's deep feelings; there is no match between the two" ("Shidao huange"); Huang Tingjian (1045–1105) had a poem: "While my mouth may not be unable to utter what I am feeling, my heart is really content with what I have appreciated" ("Pinling"). Also, a Buddha in the Lotus Sutra: "Stop, stop! There is no need to utter anymore since my dharma is so marvelous and it is impossible to convey it to anyone" (Miaofa lianhuajing, "Fangbian"). Meanwhile, expressions of this kind are: "my feelings can hardly be described in any language", "it is hard to find someone who can really appreciate what I have meant", "my language fails to express my idea" so on and so forth.
更为典型是陶潜的《饮酒》：“此中有真意，欲辩已忘言”；而陆机的《文赋》：“恒患意不称物，文不逮意”，透露的则是一种作者与语言之间永恒的挣扎。
More typically, Tao Yuanming (365–427) said in his "Poems after Drinking Wine": "There are certain things that move me deeply, which I would like to tell but at the very moment I lose the words". The critic Lu Ji (261–303) had a comment in his Rhapsody on Literature: "My constant concern is that my ideas may not have reflected the objects accurately, and my writing may be deficient of my abundant ideas", revealing a constant struggle between an author and his language.
著名学者钱钟书论道：“谈艺时每萌此感。听乐、读画，睹好色胜景，神会魂与，而欲明何故，则已大难，即欲道何如，亦类贾生赋中鹏鸟之有臆无词。巧构形似，广设譬喻，有如司空图以还撰《诗品》者之所为，纵极描摹刻画之功，仅收影响模糊之效，终不获使他人闻见亲切。是以或云诗文品藻只是绕不可言者而盘旋”（《管锥编》）。
As the well-known scholar Qian Zhongshu points out, "Discussing literatures or arts often causes the same frustration. When listening to music, viewing a painting, or enjoying fabulous scenery, your heart and soul are merged with the things that have been perceived. Yet it is almost impossible for you to describe and convey what you have been moved by at the spot; if you do that, you may end up resembling the roc in Jia Yi's poem where he could not put his thoughts into words properly. Or, if you imaginatively construct a delicate framework of analogies where abundant metaphors and figures of speech are presented, as Sikong Tu did in his Modes of Poetry, you may have drawn or caved a replica vividly, but still only fashioned a resemblance which never affects others to have the same aesthetic experience as you had. That is the reason why it has been widely agreed that literary criticism, for instance, should basically never be expressed in words; it can only be circled around in the field" (Limited Views).
当代作家章诒和亦有一段刻骨铭心的描述：“我拿起笔，也是在为自己寻找继续生存的理由和力量，拯救我即将枯萎的心。而提笔的那一刻，才知道语言的无用，文字的无力。它们似乎永远无法叙述出一个人内心的爱与乐，苦与仇”（《往事并不如烟》）。正如刘勰在《文心雕龙·神思》中所说：“思表纤旨，文外曲致，言所不追，笔固知止”。
The contemporary writer Zhang Yihe has a heartbreaking writing: "By writing this book, my desire was to relieve my dying heart and to gain some strength and purpose for my survival. However, I was dead wrong! The moment I picked up the pen, I realized how powerless and useless the words, the language!…I doubt they can ever convey a person's true love, joy, pain or hatred" (The Past Events Have not Vanished like Smoke). This has proved literary critic Liu Xie's (465–522) point in his Dragon Carvings on the Literary Mind. "The delicate nuances of language lie at the boundaries of thought and the subtle meanings of a sense of feeling beyond any written words: this is where a speech is held back from its further pursuit and a pen halts without a clear realization".
同时，语言一旦形成，又有其相对的独立性和多面性。例如，墨子的说“言多方”，“行而异，转而危，远而失，流而离本”（《墨子·小取》）；吕不韦言：“言不可以不察”，“多类非而是，多类是而非”（《吕氏春秋·察传》）。而这从另一方面证实了语言的“不可靠性”。
Meanwhile, once a saying is formed it becomes independent and multifaceted. As Mozi said that "Utterance has many meanings", "As the language is being conveyed its meanings may vary gradually; as it changes its course, it may damage someone. When it is carried far away, it will be lost somewhere; when it is set adrift it will deviate from its original route" (Mozi, "Xiaoqu"). Also, the historian Lü Buwei pointed out in his The Spring and Autumn Annals of Lü: "Words cannot go without being scrutinized", "More often than not words appear to be one thing but turn up to be another". These comments have illustrated the "unreliability" of a language from another prospective.
总之，理解语言的局限性，其实有利于我们更深刻地认识和掌握语言。
In short, by realizing its limitations, we may in fact gain certain insights in mastering a language.