고대 중국어에서 ‘聲’과 ‘音’은 동의어로 여러 가지 동의 관계를 나타낸다. 보통 ‘聲’은 일반적인 소리 혹은 자연의 소리를, ‘音’은 거기에 ‘音’과 박자를 가미한 인공적인 소리 혹은 음악을 나타낸다. 또는 ‘聲’을 ‘宮商角徵羽’ 가운데 하나의 단음으로, ‘音’을 이들이 어우러진 和音으로 설명하기도 한다. 하지만 이러한 ‘聲’, ‘音’의 동의 관계가 《老子》의 “大音希聲”, “音聲相和” 구를 이해하는 과정에서 난관에 봉착하게 된다. 본문에서는 《詩經》등의 문헌을 통해 《老子》당시에 통용되던 ‘聲’, ‘音’의 동의 관계, 즉 ‘音’은 발성체에서 나오는 소리를, ‘聲’은 귀로 들리고 전해지는 소리임을 밝히고, 이에 근거하여 두 구의 의미를 원만하게 풀어내고 있다.

In ancient Chinese, ‘Sheng(聲)’ refers to general sounds or natural sounds, while ‘Yin(音)’ refers to artificial sounds or music with added rhythm and melody. Alternatively, ‘Sheng(聲)’ has been explained as a single note among the five tones[宮商角徵羽], while ‘Yin(音)’ is described as a harmony created by their combination. However, these synonymous relationships were insufficient to explain the phrases ‘Dayinxisheng(大音希聲)’ and ‘Yinshengxianghe(音聲相和)’ in the 《Laozi(老子)》. While ‘Dayinxisheng(大音希聲)’ could still be explained through existing synonymous relationships, the phrase ‘Yinshengxianghe(音聲相和)’ must satisfy several conditions beyond mere synonymy according to the context. These conditions include mutual opposition, mutual dependence, mutual substitutability, and mutual equivalence, which are difficult to explain using only traditional synonymous relationships. In the 《Shijing(詩經)》, ‘Yin(音)’ and ‘Sheng(聲)’ provided crucial clues through a rich variety of examples. ‘Sheng(聲)’ referred to sounds that are heard by or transmitted to the ear, whereas ‘Yin(音)’ referred to sounds produced by a vocal source, including the human mouth. The synonymous relationship between ‘Yin(音)’ and ‘Sheng (聲)’ found in the《Shijing(詩經)》satisfies all the necessary conditions for explaining not only the phrase ‘Dayinxisheng(大音希聲)’ but also ‘Yinshengxianghe(音聲相和)’ in the 《Laozi(老子)》. Furthermore, since the 《Shijing(詩經)》was composed in a period close to that of the 《Laozi(老子)》and its usage is verified through actual literary examples rather than mere theory, it can be said to possess high objective validity.