The three phases of solar terms in beginning of autumn were in ancient times. The ancients divided beginning of autumn into three phases, one for the cool breeze, the other for the dew, and the third for the chilling sound.
When a cool breeze arrives, it means that the cold wind in the west is called cool breeze, and the temperature changes and the chill begins to subside. In other words, the wind at this time is no longer the hot air in summer, and the weather is beginning to turn cold.
Second, when the white dew falls, it means that after the heavy rain, the cool wind comes, but the weather drops in a vast and white way, and the beads have not yet condensed, so it is called the white dew, which shows the white color of autumn gold. In layman's terms, it is the fog that begins to appear on the ground in the morning.
Three waiting for the cicada to sing means that the cicada that sings in autumn also begins to sing. Cicada began to sing, indicating that the weather is really getting cold. Cicada is a signal to autumn, just like a cuckoo is to summer.
Historical origin