They say a reader lives a thousand lives and those who don't live one. Well, I don't know that 'they' say it, but I like the phrase a lot.
I've written before about the value of vicarious experiences; we use other peoples' experiences to build our expectations of the world. But empathy isn't an easy thing to learn from others. Unless you have particularly emotionally vocal mates, then it's unlikely you're going to learn a great deal about how other people experience emotions.
You can be an expert in how emotions work and what they're for, but without knowing what's going on in the person's mind (and you're super bad at knowing what's on peoples' mind) you're going to find it hard to deduce how they're feeling.
Books teach us empathy (but not all books)
Well, it turns out that books are a fabulous place to get those insights. Those who were assigned fiction books to read consistently scored higher on their ability to identify emotions.
But not just any kind of fiction. Popular fiction doesn't cut it. Literary fiction is the key - fiction that explores the human condition or comments on society and politics; fiction that holds literary merit. The researchers explain that these kinds of books leave 'gaps' in the story and importantly, in their characters. This forces the reader to bridge those gaps and in completing the character's picture they grow in their understanding of the mind. As the researchers put it, these books don't just simulate social experiences, they are a social experience.
This idea follows along nicely with a theory that's been guiding all our schooling for decades. Lev Vygotsky is a giant of developmental psychology. One of his legacies was the hugely influential theory of the 'zone of proximal development'. The ZPD essentially refers to the space between two 'levels' of skill. Think of it like a cliff. You're at the bottom, with no way up. If someone at the top throws you a ladder, then you can climb up too. The ZPD is similar, as it relates to our mastery of skills and knowledge. We can only get so far ourselves before we reach a sort of limit in our ability to keep learning. We need someone to give us a little guidance before we can get to the next level.
In this case, the writers of literary fiction let us build a picture of a person to a point, and with a little guidance we're able to complete that picture, thus learning a little bit about how different people have different perspectives. Do this enough and our skill grows, bolstering our empathy and our Theory of Mind. So, pick up a book. It'll make people like you more, it's science.