"If being good at Divination means I have to pretend to see death omens in a lump of tea leaves, I'm not sure I'll be studying it much longer! That lesson was absolute rubbish compared with my Arithmancy class!"
-- Hermione Granger (PA6)
Arithmancy is a branch of magic that is concerned with the magical properties of numbers; someone who practices Arithmancy is called an Arithmancer.
Arithmancy is offered to Hogwarts students after their second year (PA12, Pm). Hermione attempted an O.W.L in Arithmancy and received an Outstanding (HBP5).
Bridget Wenlock was a famous 13th century Arithmancer. She discovered the magical properties of the number seven (BoS).
Books about Arithmancy include:
"Arithmancy" is derived from the Greek arithmos (number) and manteia (divination). Historically it's the study of numbers connected to the letters of a name or the birthday month in order to foretell someone's future (source: Wikipedia) That makes it quite ironic that Hermione viewed Professor Vector's class as superior to Trelawney's since both are about Divination.
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Tags: Hermione Remembrall math numbers seven