"This takes the issue of sex and looks at it from a completely different angle. A wizard who is about to die can pass his staff to a sucessor, typically the eighth son of an eighth son. Unfortunately for this wizard, the eighth son turns out to be a girl and all sorts of trouble follows. So why can't a woman be a wizard (apart from the issue of plumbing, of course)? It is written in the lore and there is a perfectly self evident answer that no-one can recall right now. Another very funny take on real life in an unreal world.