Board Thread:Theories and Speculation/@comment-12509038-20150119062617/@comment-8284722-20150123161845

Recently re-read Chapter 698, and it turns out I kinda skipped over what Sasuke said there. It's pretty brief, and as such it's rather vague. Sasuke mentions that an "eternal destiny" Hagoromo mentioned PROBABLY ends. And we don't know what exactly he was referring to.

What I meant by social classes is that it's the only way to move up or down the caste system. For example: if you're an untouchable and you want to marry a Brahmin for higher social status - you can't. You have to be reincarnated as a Brahmin. It sucks, but that's what they believe. I also have no arguments with the Six Paths of Pain; I was just making a trivia statement there.

Ultimately, as you said, it's very vague. Who knows? Maybe Kishi created his own form of reincarnation (Hindus are prone to creating their own concepts for their own faith - hell, some even believe in Jesus!) In this same way, the Avatar thing is probably entirely different also. Speaking of which, from what I know there's no purpose for the Avatar beyond spreading spiritual essence everytime he/she appears. I highly doubt that Korra is the final Avatar - expect a series about an Earth-native Avatar in the future.