This is hidden brain.
I'm Shankar Vedantam.
If I asked you what it means to be a good person, I'm guessing you would quickly rattle off a list of virtues.
Good people are truthful.
They are kind to others, helpful to those in need.
They are loyal friends, generous, brave.
They put the needs of others before their own needs.
But if I were to ask you where those beliefs come from or why you think kindness and bravery and generosity are virtues, you might have to pause for a moment to think.
Let's say I make it even more complicated.
I give you a scenario about two brothers who love each other dearly.
One does something wrong, and the other has to decide whether to turn him in.
The second brother must choose between honesty and loyalty.
Which virtue is more important?
If you picked one, do you know why you chose it?
Tv shows and movies are filled with these kinds of moral dilemmas because they provide dramatic tension.
When you have to choose between competing values, you might find yourself unsure if kindness matters more than courage or if loyalty should outweigh honesty.
Playwrights and poets have grappled with these themes for centuries because our moral choices define us.
They help us distinguish friend from foe.
They inform whom we love and whom we hate.
Today, we examine the roots of our moral intuitions.