======Arithmancer======
=====Introduction=====
An **Arithmancer** is a [[wizard]] or [[witch]] who practises **[[Arithmancy]]**, a specific branch of [[magic]] that involves the complicated and magical properties of numbers. The primary application of [[Arithmancy]] is a form of [[Divination]], used to predict the future through intricate calculations and numerical charts.
This discipline is presented as a more rigorous, logical, and academic form of future-telling compared to other methods such as [[Tessomancy]] (reading tea leaves) or [[Crystal Gazing]], which are often viewed as imprecise arts. An Arithmancer relies on intellect and complex formulae rather than intuition or the 'Inner Eye'.
=====The Practice of Arithmancy=====
[[Arithmancy]] is an elective subject offered to students at [[Hogwarts School of Witchcraft and Wizardry]] from their third year onwards. It is known to be a particularly challenging course, requiring a high degree of logical reasoning and academic dedication. The class involves interpreting complicated number charts and writing essays on the findings.
The subject was taught by [[Professor Septima Vector]] during [[Harry Potter]]'s time at [[Hogwarts]]. [[Hermione Granger]] chose to study [[Arithmancy]], partly because she found the vagueness of standard [[Divination]] to be frustrating. Her decision to take the class, along with every other elective, necessitated the use of a [[Time-Turner]] during her third year.
=====Known Arithmancers and Practitioners=====
While few Arithmancers are mentioned by name, several characters are noted for their connection to the practice:
  * **Bridget Wenlock:** A celebrated 13th-century Arithmancer who was the first to establish the magical properties of the number seven. (video game)
  * **[[Professor Septima Vector]]:** The [[Arithmancy]] professor at [[Hogwarts]] during the 1990s.
  * **[[Hermione Granger]]:** The most prominent student of [[Arithmancy]] in the series. She excelled at the subject and continued with it to [[N.E.W.T.]] level, finding its logical framework far preferable to Professor [[Sybill Trelawney]]'s [[Divination]] class, which she ultimately dropped.
=====Applications and Significance=====
The primary function of an Arithmancer is to predict the future. However, the principles of [[Arithmancy]] have broader applications in the [[Wizarding World]].
  * **Professional Careers:** A proficiency in [[Arithmancy]] is considered a valuable skill for certain high-level professions. [[Bill Weasley]] noted that it would be a useful subject for someone hoping to become a [[Curse-Breaker]] for [[Gringotts Wizarding Bank]].
  * **Magical Theory:** The study of magically significant numbers is a core tenet of [[Arithmancy]]. The concept of seven being the most powerfully magical number, as mentioned by [[Professor Horace Slughorn]] to a young [[Tom Riddle]] in the context of creating [[Horcrux]]es, is a principle derived from this field of study.
=====Etymology=====
The term "Arithmancer" is a direct derivation from "Arithmancy." The word //Arithmancy// itself originates from the Greek words //arithmos// (ἀριθμός), meaning "number," and //manteia// (μαντεία), meaning "divination." Therefore, an Arithmancer is literally "one who performs divination by numbers."
=====Behind the Scenes=====
  * Arithmancy, or Arithmomancy, is a real-world form of divination with roots in ancient Greek and Chaldean traditions, which associated numbers with divine or mystical significance.
  * In the video game //Hogwarts Legacy//, the principles of [[Arithmancy]] are presented as a gameplay mechanic. Numerous puzzle doors are scattered throughout [[Hogwarts Castle]], which can only be opened