World's biggest truth?

World's biggest truth? 
Every person from morning till evening only thinks about how to benefit himself. Imagine what a doctor would think when he went to his clinic. What would a beer seller think when he went to his shop? Think...
Now the question is that when no person in the world likes to move ahead with you, then why do big people open the big secrets of their life in front of people. Have we ever thought...

100% of the people of the world know that reading is necessary for life but still 90% of the people do not study.
In childhood, we have heard a line many times that it is easy to speak and difficult to do.
The main premise of Lord Buddha's Eightfold Path is focused on Truth. Tattva or truth is contrary to fiction. At present, many people or teachings tell the method of imagination or visualization which is not correct. Truth means that which is happening. If the ultimate knowledge is to be known, it begins with accepting the truth.