>But it's not really practical to interact with characters by appealing to love, greed, loyalty, arrogance etc. in order to motivate them to behave differently

>But it's not really practical to interact with characters by appealing to love, greed, loyalty, arrogance etc. in order to motivate them to behave differently You can do something like that in Deus Ex: Human Revolution. You can have a cybernetic augmentation that lets you read microexpresions and do voice analysis. Then it tells you if the character you are talking to is more likely to be persuaded by flattery, assertiveness, bribery, intimidation and so on. It ends up being little more than a gimmick, because being a modern high-budget game with impressive actors (they do good voices and their face expressions are so realistic that you don't need that cybernetic augmentation if you know how to read expressions in real life), it would be too expensive to have the kind of huge conversation trees that old style text-based computer games have.