The Doctrine of Triangles

“Glen van Brummelen has prepared a highly recommended, accessible and definitive history of the subject that will serve as a resource for scholars for decades to come.”—Daniel Otero, MAA Reviews“

The Doctrine of Triangles is an informative and valuable reference work.

”—Wallace A Ferguson, Institute of Mathematics and its Applications“A guided tour through the museum of mathematics… . [The Doctrine of Triangles] takes the history of trigonometry, which is a formidable subject in its scope and size, and transforms it into something readable.”—Daniel Mansfield, The Mathematical Intelligencer“Very easy to read, and there are lots of helpful diagrams, especially for the spherical trigonometry … [The Doctrine of Triangles] is deeply enriched by extracts from contemporary texts, given first in fairly literal English translations, often accompanied by the original diagrams, and then explained in modern terms. So mathematical readers (and, I hope, their students) can experience a little of what trigonometry was actually like at each stage in its history.”—John Hannah, Aestimatio