I tend to think the characters of Discworld that come off as "nongood" are actually, most often, putting on a sham. The reason being that REALLY nongood people tend to take advantage of goodness when they know it's there. Thus, a wise good person in Discworld generally tries to conceal their basic decency.
The exception is Carrot of course. He's SO good that even evil characters start acting good around him, negating the danger.
Some convincing arguments can be made in favor of Vetinari being evil...but I don't buy it. His training in the Assassin's guild is often brought up, but I'm not sure that that proves he really killed anyone. It's oft repeated that noble families often train their scions with the Assassins; not so they'll be killing machines, but because it's prestigious (and perhaps increases their odds of survival later). Morever, when I look at how he rules...yes, he's manipulative, but almost every single one of his manipulations are to make sure that horrible selfish greedy people are so busy watching their backs and feuding with each other that the common man has little to fear from them. In short, his motivation is not self-aggrandization, as an Evil man's would be. His motivation appears to be genuine concern for the well-being of Ankh-Morpork...and ALL the people in it. To that end, he uses the 'tools' at his disposal...tools like Vimes. You could accuse him of being detached from humanity...I think anyone with his superintelligence WOULD be. I'd tend to point out too that even his actions in manipulating "good" people like Vimes tend to work out in the person's best interest, and he's been known to have compassion though you have to really understand him to know when he's displaying it.
-- In short, Vetinari is the picture perfect example of what I'm talking about. I think he's really Good. As Good in his own way perhaps as Carrot is in his. Definitely Neutral Good, since law and order are merely tools in his arsenal for himself...even if they're also what he seeks to impose on others. I think every intimation of torture and deadliness he surrounds himself with are all part of a carefully managed self-image that he projects so that he doesn't HAVE to use torture and killing. His job description is to keep the low-lifes (who are usually the rich and well to do) from preying on the helpless and making Ankh Morpork into their personal feeding ground. So he HAS to seem hardcore. Unrelentingly hardcore. I argue that his actions (and I count only the actions that occur within the narrative...anything else could just be a self circulated rumor) do not bear this image out.
Same thing with Susan, Death, Vimes... All of them have this crusty outer shell where they pretend not to be motivated by compassion and goodwill. This protects them from those who would capitalize on that goodwill and use it against them...of which Discworld is FULL of. Death started out the true picture of Lawful Neutral, but his adventures with Mort, Alfred, and later Susan have sensitized him to humanity and the human condition. I would argue that he now sees his job as the epitome of -compassion- for us, and that is how he keeps doing it. He believes that he's just as impartial as he ever was...but again, his actions belie it. He cares now...cares enough to risk whatever he is on our behalf. Susan always cared, but had a rough childhood. She's fiercely independent and hates relying on anyone but herself...because anyone else can let her down. Yet look at how she treats children. With respect...as equals. She shields them from the schoolmistress and her misguided ways. Her desire to be 'normal' leads her to be reluctant to intervene on 'family business,' but she always takes the high road in the end.
...and I don't think anyone was actually arguing Vimes wasn't good.
Rincewind. I guess I agree he's more Chaotic Neutral. He's an oddity though, and very rarely shows up anymore. He's a relic of the Old Discworld, back when it was a parody of fantasy fiction tropes and RPG's...rather than a parody of reality and human nature.
