Board Thread:General Discussion/@comment-26173936-20150328173404/@comment-27159736-20150724160917

In the AMA he says that "Edwin Abbott Abbott has a good idea" Abbott wrote a novel called flatland which a novel about a  2 dimentional plane full of shapes who's popularity depends on the amount of sides and polygons are worshiped while triangles are outcasts.

This can mean that Bill is trying the destroy the Gravity Falls universe to take it over for himself or to gain respect or authority from his piers from the nightmare dimension.

I think Society of the Holy Mackerall explains this better than I do.