Prophecy Pub/Less Than The Meanest Ghost/Black Family Tree

[pippin_999]

Pippin:
> > I remind you (again) that Slytherin was noted for his disregard of 
> > rules. Certainly there are loads of Slytherins who aren't "of great 
> > cunning" so why couldn't the Hat be just as flexible about pure 
> > blood?

Nora:
> 
> Well, still going with the scanty canon that we have, it was the 
> blood issue which broke the whole alliance of Founders down, wasn't 
> it?

Pippin:
Was it? The Hat's information is surely at least as reliable as Professor
Binns's, and it says the alliance broke down because the Houses 
"Now turned upon each other and,/Divided, sought to rule."

The Hat contains the brains of the younger Slytherin, the one who
who helped found a school where Muggleborns could study 
magic. He must have been more flexible and tolerant than the
person who left the basilisk in the Chamber.

Pippin