Characters for Whom You're Responsible
In The Sims, players do something more than invest the characters with life. Compared to a stuffed animal, Sims already look fairly alive, so it doesn't take an extreme amount of "investing."
Players are also responsible for their Sims. Characters for whom we feel responsible have Rooting Interest (meaning that we empathize with them).
You can see this even in real life, for instance, parents suffer when one of their children experiences a major setback or disappointment.
Going back to our game with the dragon: You come to know the villagers, and they depend on you to save them. Assuming they're made life-like enough and with techniques to give them Rooting Interest, you want to save them. You feel responsible for them. This increases your empathy for each of them.
Take a look at another example.
In the hypothetical game illustrated on the following page, you play Jen Cranston, a surveyor under contract with the government of Peru. Your life is pretty drab and uneventful, until you get lost one day (which happens to be where our game begins) and hear screams from inside a cave.
You explore and discover this ancient artifact, as well as Citlali, the woman who's been trapped by it and who's been writhing in pain for 1,000 years.
You smash the artifact and free the woman from her agony.
It's true that empathizing with someone leads us to wanting to have some responsibility for them. But the reverse is also true: taking responsibility for someone causes us to empathize with him or her. In this case, you'd empathize with the woman for whom you took responsibility, and whom you liberated from her torment.
We can see this in life not just with parents and children, but even with pets. If you take care of a dog or cat, soon you start empathizing with it. Thus, if the animal gets sick or wounded, it will affect you emotionally.
The parameter of our being expands to encompass those people, and even animals, trees, and things, for whom and which we feel responsible. For them, we'll feel empathy. This is that almost mystical ability I noted at the start of the chapter our ability to see through the eyes of others.
Citlali also has Rooting Interest due to two other techniques. First of all, she's in Danger and an NPC in Danger is one we're likely to identify with. Additionally, she has Undeserved Misfortune, which also gives her Rooting Interest. (To be fair, we don't yet know if Citlali's misfortune is undeserved or not, although the way I envisage the game, she wouldn't have deserved this punishment. And even if, later in the game we learn that her misfortune is deserved, she'd still have Rooting Interest until then.)