You entered your platform, there is time for your train to left, you saw train is departing, a person is running to catch the train, you stuck there watching him, finally he was able to board the train, you felt happy and relax, you don't know why? you don't know the person, you don't know his journey, you don't know his destination yet you felt happy for an unknown human being with unknown features, perhaps this empathy is second nature to us, so much so that anyone devoid of it strikes us as dangerous or mentally ill.
Famous economist Adam smith once said "our species depends on empathy and cooperation, which means that we do better if we are surrounded by healthy, capable group mates. Taking care of them is just a matter of enlightened self-interest."
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