Having the courage of your convictions is important.
4th Edition is full of bold moves towards a new philosophy of game design. It makes many sweeping changes to Dungeons & Dragons, and is unapologetic. But there's a few places where it seems hesitant - where it knows it needs to change, but seems unwilling to let go of the past.
One of these is alignment.
D&D's treatment of alignment is infamous. Past editions have posited that all ethical and moral codes can be pigeonholed into one of nine squares on a three-by-three grid. An individual is either Good (self-sacrificing), Evil (selfish) or Neutral (governed by enlightened self-interest). Simultaneously they are either firm adherents to a social contract (Lawful), wilfull sociopaths (Chaotic), or pragmatists who follow rules so far as convenient (Neutral).
This charmingly simple ideology gives a lot of flavour to early editions of D&D, and its concept of morality as an easily defined matrix is very attractive to the mid-to-late-teen demographic of the hobby. However, it's been holding the game back in a number of ways.
By presenting nine alignments, the game implied that all nine were valid choices for player characters. The sort of players most inclined to play Chaotic Evil characters were typically those least suited to play them. "Roleplaying your character" in the context of evil PCs was often translated into "being a jerk", and party after party lost sight of the game's core dungeon-crawling gameplay amid internicine morality wars and backstabbing. Rather than encouraging roleplaying, the alignment system ended up straightjacketing players into some decidedly odd patterns of play.
4th Edition tries to throw alignment out the window. The developers have looked around and seen that no one else in any medium is using this mechanic. Dungeons and Dragons has found its way to a lonely little ideological island where the roleplaying mainland is only barely in sight.
Moreover, the developers have remembered what Dungeons and Dragons is good at. It's about heroic fantasy, with the emphasis on heroic. If the players aren't running heroes then they need to take a good hard look at why they're playing the game in the first place.
To this end, the alignment system has been pared down. The nine point system is gone. In its place is a continuum with five divisions. There's Lawful Good, plain old Good, Neutral, Evil, and the mad cackling extreme of Chaotic Evil. The two evil alignments are specifically forbidden to players. The book is explicit - you can make a regular hero, or an anti-hero, but by Pelor you're going to make a hero.
Gone too are most of the mechanical effects of alignment. Paladins are no longer required to be Lawful Good. There are no weapons that can only be wielded by those of correct alignment. Even the Great Wheel of the Planes, where each alignment was represented by a heavenly realm, has been cast aside in favour of a confused bipolar scatter of worlds.
It's a great improvement. It theoretically opens the door to more types of character, and more types of story. Players can play their character as they feel they should without stopping every five seconds to debate whether they are correctly representing their alignment. Paladins are as narratively interesting as any other class on offer.
But you have to wonder why the developers didn't go the rest of the way down the path. Why not scrap alignment altogether?
I think the answer lies in the realm of contrast. I think we still have Good and Lawful Good so that the game could retain Evil and Chaotic Evil. I think we have alignment not so the game can say, "Act like this," but so it can say, "Don't act like this."
Dungeons and Dragons is not a game of greys; it's a game of black and white, and by retaining the extremes of the alignment system it's drawing a line, and telling us which side the players should be standing on.