I put it like this: if you think the main point of a Yasumi Matsuno game is that there is no black & white, then you are a Matsuno character stuck inside one of his games.

Nearly all of the Ivalice stories chronicle how the protagonists are able to rise above and transcend the moral ambiguity that dominates their setting.

I suppose you could argue that Vayne is simply a product of the harsh environment he is apart of. And he obviously does believe in the strong have the will to power type philosophy of power politics, and that he thinks that is best. But being caught up in that is his sin, he's unable to see through the fog on his blind quest for power.

It's really sad at the end when (SPOILER)you see all the characters when they're younger and you think about how they were to become or the things that would happen to them