1, literally:
Everyone in the world knows what the standard of beauty is, so it also determines the standard of relative ugliness; Everyone in the world knows what the definition of good is, so the opposite definition of evil is determined.
2. Practical significance:
For example, if we set a standard or definition for beauty, then the opposite standard and definition is ugliness. In other words, when we define beauty, we actually define ugliness. When we define good, we also define evil, because the opposite of the definition of good is the definition of evil.
For example, if we define that it is good to harm others and benefit oneself, it is equivalent to saying that it is evil to harm others and benefit oneself. Positive is negative, and positive is negative.
Extended data:
I want to emphasize such a relationship just to illustrate the objective fact that there is a mutual relationship between two groups of concepts or things with opposite nature or content.
Knowing beauty means knowing ugliness, and knowing good means knowing evil. Knowing why, knowing why, so concepts or things such as existence, difficulty, length, competition, and context are mutually generated.
Therefore, there is beauty and ugliness; Where there is good, there is evil; There are high and low; Where there is difficulty, there is easy. In Lao Tzu's original words, it is "whether there is mutual complementarity, difficulty and complementarity, different length, oblique height, harmony of sound and sound, and difference before and after".