Dialogue is the key because it leads to actions that are also measured on the scale of good and evil. On Tattoine when you visit the Sand People's village, you have several objectives on your list of things to do if you want to advance in the game. This is a situation where your conversation skills are crucial because you're using a translator (your hilarious homicidal droid companion; we'll have more on him another time) and he warns you that you'd better choose your words carefully in dealing with the chieftain. It's times like this where your rudeness will offend the other party so much that a fight will break out right then and there with no more conversation to follow.