The system, as D&D describes it, is pretty stupid. I prefer the way Megami Tensei uses the system. Lawful people want, essentially, safety and order even at the cost of freedom. Chaotic people value freedom more, though it means losing the laws and order that protect those who can't protect themselves. Neutral people are a lot less common because of this (most people lean one way or another on this argument), but the few neutral people there are either uncompromising idealists, or people who just don't care. Good is called Light and just refers to having compassion for others and enjoying helping them, Evil is Dark and is for anything ranging from selfishly not caring who suffers so long as you get what you want, to actually enjoying hurting other people, and Neutral mostly consists of self-interested people who aren't outright selfish and show a decent amount of empathy.
People end up falling all over the chart with that system, and I think it's just a lot easier to relate to than the "Evil means you worship devils" sort of thing D&D goes for.
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Ace Detective in Sir Chris' Police
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