What is the meaning of the couplet "Three talented people in heaven and earth, thinking about poetry and elegance"?

"Three talents in heaven and earth and people, an ode to poetry and elegance" are usually "three lights, sun, moon and stars, ode to elegance in four poems". Of course, some people also use "three talents in heaven, earth and people, ode to elegance in four poems". The "three talents" refer to heaven, earth, and people; the "four poems" refer to the four parts of the Book of Songs: "Daya", "Xiaoya", "Guofeng" and "Ode".

In the previous sentence, there are "three lights, sun, moon and stars"; in the next sentence, "Ya" is used as "Daya" and "Xiaoya". The word "Ya" can be used as "Daya" and "Xiaoya". Together with "Wind" and "Ode", it is combined into four poems. It is said that Su Shi sent envoys to the Liao Kingdom, which is based on the words of a novelist and cannot be trusted. In fact, neither the upper couplet nor the second couplet meets the requirements of the couplets being square and flat. However, if the above three couplets are numbers, it is easy to pronounce the upper sentence and difficult to pronounce the second sentence. The numbers in the first couplet are free, but the numbers in the second couplet are different from those in the first couplet. The words of the things mentioned do not match, but the content must match. This kind of couplet is extremely difficult and challenging.

The following are some such coincidences of numbers:

The Four Great Heroes of the Tang Dynasty, Yang Luluo

The Fifth Son of the Song Dynasty, Zhou Cheng, Zhang Zhu

People There are seven emotions, joy, anger, sorrow, fear, love, evil and desire

The six arts are preserved in the scriptures, poetry, etiquette and music change the Spring and Autumn Period