Why do humans forget?

1. Function of brain to survive

 Why do humans forget?

If the superhumans who don't forget everything was born by mutation, they will drive out ordinary humans?
The function of brain to forget is useless or useful for us to suvive?

All humans on the earth can forget from a long lomg time ago, and superhumans have never been born.
There might be some reasons, and they are maybe evolutionary.

2. Some hypotheses

 I try to think some hypotheses about that question.

(1) Capacity of brain

 The brain of humans have a limit to remember something.
So it's necessary for brain to forget.

For example, computer also has a limit of its memory.
If we can't save the data because of the shortage of memory, we need to delete any other data.

(2) For selection of information

 It's useful for brain to forget in order to select important information from all data.
The function to forget is a part of the whole design of brain.

If we have to remember all data from the external world, the data will be too big, so maybe we can't organize and use them.
If brain can forget, we can delete useless data naturally.

Of course we have to remember important information.
So brain can decide that the data which we use again and again must be important, and will remember it.
The very important information will transfer from short-term memory to long-term memory.

3. Check the answer

 I searched on the internet about this question.
I think this article is most readable and interesting.
・It turned out that the brain positively 'is about to lose memory' (GIGAZINE)

This kind of research is very interesting.
Science and technology have highly developed, but there are many mysteries in our body.

The mysteries have been waiting for you.
Young scholars and researchers!

- To read this article in Japanese