Pappus of Alexandria (c. 300–c. 350)

Greek mathematician, astronomer, and geographer whose book Synagogue/Collection deals with nearly the whole body of Greek geometry, mostly in the form of commentaries on texts the reader is assumed to have to hand.

Nothing is known of his life and many of his writings survive only in translations from the original Greek.

Without the Collection, much of the geometrical achievement of his predecessors would have been lost for ever.

It reproduces known solutions to problems in geometry, and also frequently gives Pappus' own solutions, or improvements and extensions to existing solutions. For example, he handles the problem of inscribing five regular solids in a sphere in a way quite different from Euclid.

Among Pappus' other works are a commentary on Ptolemy's Almagest and a commentary on Euclid's Elements. Pappus is also believed to be the author of the Description of the World, a geographical treatise that has come down to us only in Armenian and bearing the name of Moses of Khoren as its author.