Obelus (÷) as a division sign
Óbelo (÷) como signo de división
- Date
- 1659 · confidence medium
- Place
- Zurich, Switzerland
- Credited to
- Johann Rahn
- Field
- Knowledge & symbols
What it is
The ÷ sign adopted as a symbol for mathematical division, derived from an old manuscript annotation mark (the obelus) also used as a typographic dagger and a commercial minus sign.
Introduced by Swiss mathematician Johann Rahn in his 'Teutsche Algebra' (1659) and spread in English through John Pell's translation (1668).
What it led to
- Standardized arithmetic notation in English-speaking countries
- International confusion from its different use elsewhere
Built on
- 17th-century European algebraic notation