Adam Smith begins his The Theory of Moral Sentiments (1759) by observing:
How selfish soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortuneof others, and render their happiness necessary to him, though he derives nothing from it except the pleasure of seeing it. Of this kind is pity or compassion, the emotion which we feel for the misery of others, when we either see it, or are made to conceive it in a very lively manner. That we often derive sorrow from the sorrow of others, is a matter of fact too obvious to require any instances to prove it; for this sentiment, like all the other original passions of human nature, is by no means confined to the virtuous and humane, though they perhaps may feel it with the most exquisite sensibility. The greatest ruffian, the most hardened violator of the laws of society, is not altogether without it.
As we have no immediate experience of what other men feel, we can form no idea of the manner in which they are affected, but by conceiving what we ourselves should feel in the like situation.
Now neuroscience is confirming Smith's insights into the neural bases of human morality. One of the more fascinating discoveries is mirror neurons. Mirror neurons are brain cells that react when a monkey grasps an object and also react the same way when the monkey sees someone else grasp the object. It appears that humans have an even more advanced version of the mirror neuron system which enables us learn by imitation and also enables us to feel empathy. LiveScience reported:
"Mirror neurons suggest that we pretend to be in another person's mental shoes," says Marco Iacoboni, a neuroscientist at the University of California, Los Angeles School of Medicine. "In fact, with mirror neurons we do not have to pretend, we practically are in another person's mind."
However, in evolutionary time, human morality developed as a way to guide our ancestors' interactions among a relatively small group of people. Thus our moral sentiments are strongly activated when we see the plight of people in front of us. Smith captured this insight when he observed that upon hearing of the destruction of millions of Chinese via an earthquake, a European of his time would
....express very strongly his sorrow for the misfortune of that unhappy people, he would make many melancholy reflections upon the precariousness of human life, and the vanity of all the labours of man, which could thus be annihilated in a moment...And when all this fine philosophy was over, when all these humane sentiments had been once fairly expressed, he would pursue his business or his pleasure, take his repose or his diversion, with the same ease and tranquillity, as if no such accident had happened.... If he was to lose his little finger to-morrow, he would not sleep to-night; but, provided he never saw them, he will snore with the most profound security over the ruin of a hundred millions of his brethren, and the destruction of that immense multitude seems plainly an object less interesting to him, than this paltry misfortune of his own.
What accounts for this difference in moral response? The Washington Post recently ran an interesting article which reported some neuroscience research that might help explain the difference in how we respond to our neighbors and to people living far away.
Neuroscience research, [Harvard researcher Joshua] Greene said, is finally explaining a problem that has long troubled philosophers and moral teachers: Why is it that people who are willing to help someone in front of them will ignore abstract pleas for help from those who are distant, such as a request for a charitable contribution that could save the life of a child overseas?
"We evolved in a world where people in trouble right in front of you existed, so our emotions were tuned to them, whereas we didn't face the other kind of situation," Greene said. "It is comforting to think your moral intuitions are reliable and you can trust them. But if my analysis is right, your intuitions are not trustworthy. Once you realize why you have the intuitions you have, it puts a burden on you" to think about morality differently.
As Greene points out, as we better understand the limitations of our evolved neuro-morality mechanisms, we can change how we "naturally" react to the plight of human beings we don't personally know. We can use reason to include them in our circle of empathy. In addition, modern media helps expand our circle of empathy by bringing into our homes scenes from wars, tidal waves, earthquakes, and hurricanes that prompt us to see distant people more like neighbors who are worthy of our help.