One night, Thales, an ancient Greek philosopher, saw the sky clear and observed the stars on the grass. He looked up at the sky and walked slowly. Unexpectedly, a deep pit appeared in front of him. As soon as he stepped on it, he fell like a stone. When he realized that his body had been soaked in water, although the water only flooded his chest, it was two or three meters away from the road.

Can't get out, can't get up, can only shout for help.

Terez was rescued from a puddle by passers-by. He stroked his injured body and said to passers-by, "It's going to rain tomorrow! Passers-by smiled and shook their heads, telling Thales' prediction as a joke to others. The next day, if it rains, people admire Thales very much Some people don't think so. They said, "Thales knows things in the sky, but he can't see things under his feet."

Two thousand years later, the German philosopher Hegel heard this story of Thales and said a famous saying: Only those who lie at the bottom of the pit forever and never look up at the sky will not fall into the pit!