Theory:

     But the disciple wouldn’t listen to the guru’s wisdom. He wanted to stay. The guru finally gave up and said, “Do what you want. I’m going,” and left. The disciple stayed on, ate his fill every day — bananas and ghee and rice and wheat, and grew fat like a street-side sacred bull.

     One bright day, a thief broke into a rich merchant’s house. He had made a hole in the wall and sneaked in, and as he was carrying out his loot, the wall of the old house collapsed on his head and killed him on the spot. His brother ran to the king and complained, “Your Highness, when my brother was pursuing his ancient trade, a wall fell on him and killed him. This merchant is to blame. He should have built a good, strong wall. You must punish the wrongdoer and compensate the family for this injustice.”
Explanation:
 
The disciple did not listen to the guru's words. He desired to stay in the fool's kingdom. Later, the guru realised that his disciple was not going to accompany him in any case. So he decided to leave the city and told his disciple “Do what you want. I’m going".
 
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The guru left the city
 
The disciple stayed in the city for several days. He consumed as much as he could. Every day, he ate bananas, ghee, rice, and wheat to keep his tummy full. Because of the low price, he ate whatever he wanted and eventually grew fat. At last, the disciple became like a street-side sacred bull. Here the phrase “street-side sacred bull” meant that he would chew the food like a bull and seemed to sit simply without doing any work. It made him fatter than he had been previously.

Later, on a bright day, a thief came to steal things from a merchant’s house. Since the people in the foolish kingdom would sleep during the day, the burglar would prefer to steal at that time.
 
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A thief
 
The thief then made a hole in the wall to enter inside the merchant's house. After plundering the house’s valuables, he came to escape through the hole. Unfortunately, when he attempted to exit, the ancient house wall collapsed on his head. The thief eventually died.
 
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The thief made a hole in the wall
 
Then the thief's brother ran to the king’s palace to seek justice. When he met the king, the thief's brother said that the wall had fallen on his brother’s head while he was pursuing ancient trade. The term “ancient trade” signifies theft or stealing someone's wealth. The king’s stupidity was well known throughout the city. So the thief’s brother took advantage of the king’s foolishness and claimed that the merchant had built a weak wall, which was the cause of his brother’s death. The thief’s brother said that his brother would not have died if the merchant had built a sturdy wall. As a result, he petitioned the king to punish the merchant for constructing the weak wall and give justice by compensating his family.
 
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The thief's brother ran to the king’s palace to seek justice
 
Meanings of the difficult words:
 
S.No
Words
Meanings
1
WisdomThe quality of having experience, knowledge, and good judgment; the quality of being wise
2
MerchantA person whose job is to buy and sell products in large amounts, especially by trading with other countries
3
Sneak inTo go somewhere secretly, or to take someone or something secretly
4
LootTo steal something from a place or person
5
CollapseOf a building having fallen down or given way
6
Wrongdoer A person who behaves illegally or dishonestly; an offender
7 
Compensate To pay someone money in exchange for something that has been lost or damaged or for some problem
8
InjusticeA situation in which there is no fairness and justice
9
Burglar A person who illegally enter the house and steal things
Reference:
National Council of Educational Research and Training (2006). Moments. In the Kingdom of Fools– A K Ramanujan (pp. 19-24). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.