This story of an experiment was told to me by my younger brother, three years and four months younger than I am, crossed his fifty last year.
The experiment was conducted on four monkesy and was about behavioural studies.
Four monkeys (the closest cousins to humans) were put in a cage. The cage was built in a circular shape in a two story circular hall. Rods of the cage were mounted from the floor to the roof. There were several supports in between and monkeys could go up and down.
The guards fed them as per schedule for three days with different foods except bananas. After three days one of the guards hung some bananas with the roof. In no time one of the monkeys noticed them and started going up. When he reached at the roof and tried to pick the bananas from the hook one of the guard hit him with the water canon. He wasn't the only one though, the guard hit the rest of the monkeys with the water canon as well. The monkey fell down. They were all in pain by the hit. After some time another monkey went up to get the bananas, guard also hit him with the water. No more tries that day.
Next day, guards replaced the bananas with the fresh ones. Half an hour later a monkey made an attempt for the bananas, not any of the ones from the previous day. Guards repeated the water canon action and monkeys were left to bear the pain.
Three or four hours were passed when the greed started taking place in the heart of the fourth monkey and as soon as he tried to go up the rest of the monkeys pulled him back and started beating him. After some beat up, the fourth monkey gave up his greed.
For the next couple of days guards kept replacing the bananas with the fresh ones but no monkey tried to get them.
They replaced one monkey with a new one.
After getting use to his surroundings the new monkey saw the bananas hanging with the roof, then he saw the old monkeys. Without any second thought he was on his way to the bananas and eating them.
In his imaginations though.
As soon as he put foot on the first support, the three old monkeys pulled him back and started punching him. They knew what would happen if he, the new monkey, would try to get the bananas. After that the new monkey tried two more times and every time the old monkey pulled him back and beat him. No contribution from the guards.
A couple of days later the guards replaced another old monkey with a new one.
As can be guessed, this monkey was thinking himself smarter than the rest of them. He tried the same thing and the rest of the monkeys beat him up. Interestingly, he wasn't beaten up only by the two old monkeys but also by the new old monkey.
A couple of days later, third old monkey was also replaced. Again, there was the new monkey's attempt, and beat up by the rest of the monkeys.
Keep in mind only one old monkey was left who knew if anyone tried to get the bananas they would all be hit by the water canon.
In the coming days, the final old monkey who witnessed the actual incident and knew the real reason behind the punishment for getting the bananas was replaced too.
Now, the interesting part comes.
The fourth new monkey attempted the same thing, and rest of the monkeys repeated the same actions as well. But, none of them knew why they were beating him, they just did that because this was the custom. They didn't ask themselves about the logic, reason, and need et cetera for this action, they simply repeated what they learnt from their predecessors.
This is called the "Herd Mentality" or "Following the Crowd Mentality". And, this is the normal behaviour of most of us humans. We don't ask questions, we just do, we just follow.
Who do we follow?
As tarazpk has mentioned several times in his post, these are the people who make rules, who do things just for the profit/advantage of their group/s. They know the patterns how people's brains work. They control us through media and by other means. So next time, for an example, when you think you need the new upcoming cell phone of any famous brand at any cost because everyone, in your circle or not, is doing so, is in the line of getting them, ask yourself do you really need the features it offers.
As I said, Cell phone was just an example, majority of us has the same mentality about almost everything, we mostly get things because idea is being fed to us, to our brains not because we need them but because we are just following the crowd.