What is meant by human nature?

The following is an excerpt from a samvaad (dialogue) session with Acharya Prashant.

Acharya Prashant (AP): Two monks were washing their bowls in the river when they noticed a scorpion that was drowning. One monk immediately scooped it up and set it upon the bank. In the process, he was stung. He went back to washing his bowl and again the scorpion fell in. The monk saved the scorpion and was again stung. The…