Euclid's Elements, book i, by V.B. Smith

Euclid lived in Alexandria around 300 BC, under the first Ptolemy, and almost nothing else is known of him. He is said to have told the king who wanted an easier way to learn mathematics that there is no royal road to geometry.

His Elements, thirteen books on geometry and numbers built from a few definitions and axioms, has been taught for more than two thousand years. It was translated into Arabic in the age of the Abbasids, studied and improved by Arab mathematicians, and first reached Latin Europe through a translation from the Arabic.