Truths in the Wizarding World

[Ebony]

No: HPFGUIDX 7168

Hi, everyone--think this'll be my last post for the day.

After reading all four books, what would you consider indisputable 
truths in the wizarding world?  I'm making a list of them... and I 
need help.

Here's what I have so far:

All mail-—letters and parcels--are delivered by owl post.  Period.

Hogwarts is the school for magical children who live in the United 
Kingdom (and Ireland, according to JKR). 

Harry Potter is the Boy Who Lived.

I'd like to isolate about 5-10 more.  Thanks in advance!

--Ebony