One of the things that bothers me, that’s pervasive in the way adventures are written, the way PCs and NPCs are envisioned, and so on, is what appears to me to be a misinterpretation of Alignment. I’ve done a lot of thinking on the subject, but for this post I did some extra research to make sure I got things right. So first, an interesting little history lesson.
D&D, as many may know, stemmed from a tabletop wargame called Chainmail. From what I know it was a lot like Warhammer or Warmachine. Each player brings an army, you move them across the terrain and make hits against opposing units. When one player achieves some goal (occasionally simply annihilation of the opposing forces) they win. Chainmail set itself up as a conflict between Law and Chaos, and individual units were aligned to one side or the other (or neutral) so a player could decide what sorts of units made sense to include in an army together. It wasn’t about philosophy and morals so much as which side of an Epic Conflict you were on. As was noted on Grognardia, at this point the alignments might as well have been “Romans” and “Gauls.”
The original D&D game took these alignments straight from Chainmail, and like Chainmail they didn’t explain or describe what Law or Chaos meant; I imagine it was understood, since D&D was an offshoot of Chainmail, and Chainmail just used them as Faction names. (As an aside, this is why having a common language for Lawful creatures or Chaotic creatures makes sense — it’s talking about factions not ideologies, and it only follows that a faction would be able to communicate internally. Later, when alignment moves away from describing a faction, this makes less sense.) Early expansions/revisions of D&D even note that Lawful or Chaotic creatures may be either good or evil, which makes sense if the faction one is aligned to just determines what side of the conflict you’re on (rather than describing morals).
Over time this grew in to the two-axis system of alignments we know now: on one axis the line between Law and Chaos, and on the other the line between Good and Evil. The result is nine alignments ranging from Lawful Good to Chaotic Evil, and they’ve moved from simple factions to prescribing and proscribing behaviors, and some editions have even suggested penalties for veering from your stated alignment! But what does all of this mean?
The Pathfinder SRD has this to say about alignment (paraphrased): alignment is a tool to develop character identity, and each of the nine covers a broad range of personalities and philosophies. People are people, and no one is completely consistent. Good/Evil is about altruism and compassion on one side, and selfishness and callousness on the other. Law/Chaos is about honor and reliability on one hand, and freedom and adaptability on the other. Neutrality on either scale means you’re generally a good person, but you lack the conviction to make bold actions. The d20 SRD has similar things to say.
Which brings me to my point: alignment is a way of codifying in a broad way what your character’s values are. Does your character believe the needs of the many outweigh the needs of the few (or the one)? Or does your character recognize that there are winners and losers, and he’s going to do what he must to be a winner? Does your character feel that tradition, authority, and reliability are what separates us from beasts and savages? Or does she thing that a society that tries to dictate what people can and can’t do is no society worth having? Or various other philosophical approaches to Good/Evil, Law/Chaos? Two Lawful Good characters can hold sharp differences of opinion on what is means to Lawful. A Lawful Good and Chaotic Good character can have very different ideas about what “good” means.
Along with that, these are a character’s values, but they are not absolute bounds on a character’s actions. Lawful Good is not “Lawful Stupid” — it isn’t so much that he can’t lie, but that he’d rather not and would have an internal conflict if he did (since it violates a core value he holds). An Evil character isn’t incapable of helping others, but he may be angry with himself for “being soft” or letting someone take advantage of him, or not having the strength to do what must be done.
This also means that a shift in alignment has to be more than just a single counter-aligned action, or even a series of such actions — it has to be a true shift in the character’s values and perspective. This could be a gradual thing, as a character decides that his values are wrong but still feels conflicted when he offends them. Or it could be a sudden thing, the classic paradigm shift. In either case, I don’t think it’s something that should be sprung on a player unexpectedly.
As a final point, the question of “what do detect [alignment] spells detect?” often comes up. The spells themselves talk about detecting auras, and then list a table on what kind of aura various creatures leave. In d20, a regular (not cleric, outsider, or other ‘strongly-aligned’) creature under level 10 has a “faint aura”; in Pathfinder, they add that such creatures under level 5 have no aura. Which way you decide to go is something of a matter of taste and the tone you want to set for your campaign — and what the effect of such a mechanic would be. In my games, regular townsfolk are (at best) level 1 NPC-classes, and they come in a full range of alignments (based on their personal values). Using the d20 scale, detecting alignment in a crowd wouldn’t provide meaningful information because you’d pick up a sprinkling of regular people; using the Pathfinder scale, only strongly-aligned creatures or really powerful (Level 6+) mundane folk would show up with an aura. I think the latter works better for my games because it means any information you gain is meaningful information.