What does "antithesis" mean in ancient poetry?

(1) duality is also called duality. Because ancient etiquette, like a walk-on on the stage of drama now, is opposite, so it is called antithesis.

(2) Duality is a rhetorical device that constitutes neat and beautiful writing, and it is also an important factor that constitutes a metrical form and presents a metrical atmosphere.

(3) The earliest appearance: paying attention to symmetry is the characteristic of China ancient culture, from the palaces and tombs of emperors to the portals, decorations and costumes of ordinary people. Literature is no exception, because there are many monosyllabic words and even disyllabic words in Chinese, among which morphemes are quite independent and easy to cause duality, so antithetical sentences appeared as early as pre-Qin poetry.

(4) For example, The Book of Songs says: "I have been there, Liu Yiyi; The road is muddy and difficult to walk, and people are thirsty and hungry.