I suppose you could say it's become something of a curiosity. "Rightness" and "goodness" are things people speak of often, here, but for me...well, a blade's only purpose is to cut, after all.

[People don't usually understand, when he tries to explain this. But Sai doesn't really know how to be anything other than blunt.]

I understand laws, and I understand necessity. It's the third that I've yet to grasp.

[But people like Naruto and Sakura did. So perhaps he has some motivation to try to figure it out--especially in the absence of orders from Danzou.]