Dragonlance got its alignments from Greyhawk, and I wish I could say that Gary Gygax was doing a bit when he came up with this stuff - like yeah it's infantile but it's what people in the D&Dverse are taught by their ruling class so it's taken as true in-universe - but he unfortunately lived long enough to immortalize a lot of his terrible ideas on the early internet and no this really is what he came up with.