Welsh physician and mathematician.
Best known for inventing the equals sign. This was just part of his contribution towards the development and systematization of mathematical notation.
- Born: c. 1510, Tenby, Wales
- Died: 1558
- c. 1540: The Grounde of Artes, teachings the Worke and Practise, of Arithmeticke, both in whole numbers and fractions, the first English book on algebra.
- 1551: The Pathway to Knowledge, containing the First Principles of Geometry ... bothe for the use of Instrumentes Geometricall and Astronomicall, and also for Projection of Plattes
- 1557: The Whetstone of Witte, whiche is the seconde parte of Arithmeteke: containing the extraction of rootes; the cossike practise, with the rule of equation; and the workes of Surde Nombers. This is the book in which the equals sign first appears in print, as does the wonderful word zenzizenzizenzic.
Books used to have longer titles in those days.
Many sources credit his works with the first appearance of the term "algebra", but there is disagreement as to exactly which.
- ... noe 2 thynges can be moare equalle.
- 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): A List of Mathematicians in Chronological Sequence
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): A List of Mathematicians in Chronological Sequence
- 2008: Ian Stewart: Taming the Infinite ... (previous) ... (next): Chapter $4$: Lure of the Unknown