What is the difference between divination and arithmancy in Harry Potter?

Answer 1

. Many in the wizarding world consider this branch of magic to be imprecise at best. There are several types of Divination. The most imprecise is what is commonly known as "fortunetelling," and this is what Trelawney teaches at Hogwarts. The second kind of Divination is what is practiced by the centaurs. When Firenze started teaching Divination classes in the spring of 1996 [Y16], he taught these techniques, although they were mostly lost on the human students in his classes. The third type of Divination is called Seeing. This is true Divination, although what the Seer reveals is usually in the form of a Prophecy which then itself requires some interpretation. A Seer, one who possesses the Inner Eye, doesn't seem to have control over their Seeing. Trelawney, for example, only made actual Prophecies twice, although she made plenty of claims about everything from troubles ahead for various students to Neville breaking a teacup. In each case when she made an actual Prophecy, Trelawney went into a trance and spoke in a completely different voice. Both times, after speaking the Prophecy, she didn't remember a thing about it. True Seeing is very rare, but it has happened plenty of times over the centuries. There is a huge cathedral-sized room of the Department of Mysteries where records of thousands of Prophecies are stored in glass spheres. Each sphere is labeled with the initials of the Seer who spoke the Prophecy and the person it was spoken to and with the subject of the Prophecy. The record of the first Prophecy Trelawney made, which was spoken to Albus Dumbledore, was labelled as follows:

S.P.T. to A.P.W.B.D.

Dark Lord and (?)Harry Potter someone who practices Arithmancy is called an Arithmancer. For example, in the 1200s, Bridget Wenlock, a famous Arithmancer, discovered the magical properties of the number seven (fw22). An O.W.L. in Arithmancy is required to apply for a curse-breaker's job at Gringotts' (OP29). Arithmancy at Hogwarts is taught by Professor Vector. In her class, students are expected to write essays and to be able to understand complicated number charts, which are part of their homework (PA12). Hermione Granger appears to be the only Gryffindor in her year who attempted an O.W.L. in this subject (which is her favourite) (PA12, PA16).