The person doesn't know why he has a heart.
The mechanism of the brain of the person isn't often yet made clear yet.
The brain of the person evolved in the natural menace.
Oppositely, in the rich environment, it degenerates.
When seeing a troubled person, it gets to want to help.
When seeing a rich person, it is jealous.
The person may merely be being the machine (the cogwheel) which is reacting only to the status of the neighborhood actually with that it has a heart seeming.
The person by the poor society thinks that he becomes more kind than the rich society.