1, "Cao Chong said elephants"

Cao Chong, the youngest son of Cao Cao in the Three Kingdoms period, was as knowledgeable and judgmental as an adult when he was five or six years old. Once, Sun Quan sent a giant elephant. Cao Cao wanted to know the weight of the elephant, so he asked his subordinates. But they can't say how to weigh the elephant.

Cao Chong said: "Put the elephant on the big ship, mark where it reaches the water surface, and then let the ship carry other things, weigh them and compare them." Cao Cao was very happy and did it at once.

2. Sima Guang smashed the cylinder

Sima Guang was a politician and writer in the Northern Song Dynasty. When he was a child, he played with his friends in the backyard. A child climbed into the vat and fell into the water.

When the other children saw something was wrong, they all gave up and ran away, but Sima Guang used his quick wits to pick up a big stone from the ground and hit it hard at the water tank. The water gushed out and the child was saved.

3. "Dig the wall and steal the light"

In the Han Dynasty, there was a man named Kuang Heng who was diligent and studious, but his family was poor and could not afford candles. Kuang Heng has to work during the day and has time to study at night. Kuang Heng had no choice but to study hard by candlelight in his neighbor's cave, and finally he became a famous scholar by reading a lot of poems.

4. Hanging beam

In the Eastern Han Dynasty, there was a young man named Sun Jing, who was diligent and studious. He studies behind closed doors from morning till night, with little rest. Sometimes it is easy to doze off in the middle of the night.

In order not to affect his study, Sun Jing thought of a way. He found a rope, one end of which was tied to his hair, and the other end was tied to the beam of the house, so that when he was tired of reading and dozed off, as long as he kept his head down and the rope pulled his hair and hurt his scalp, he would wake up with pain.

5. "Bite"

Su Qin was a famous politician in the Warring States Period, but when he was young, he didn't have much knowledge, and no one paid attention to him in many places. Even if he was ambitious, he couldn't be reused, so he made up his mind to study hard.

Because he often reads until late at night, when he is tired enough to take a nap, he pokes his thigh with an awl prepared in advance, so that the sudden pain makes him wake up at once and cheer up to continue reading.