“...the first man in history to whom specific mathematical discoveries have been attributed.” Boyer in A History of Mathematics
Philosophy among the Greeks is believed to have begun in the Ionian city of (ca 330 BC) Mathematical Intelligencer v. 6, no. 3, 1984.
He is also credited with the discovery of the electrical properties of amber (or “electron” from which also the name electricity was derived). He was one of the to argue that Thales and the other Seven Wise Men were enthusiasts of the Spartan culture.
The common tale among the Greeks was that Thales accompanied Croesus as a military engineer in his campaigns. The Ionians, noted engineers, were employed by the eastern kings, and Thales supposedly diverted the Halys river for his employer. The Ionian philosophers sought the material principle (arche) of things, and the mode of their origin and disappearance.
It is known that Thales was asked by his mother Kleobulina to get married. He was not very interested and his reply was: O Mother I am too young to marry. This he repeated for many years until some day, when his mother again asked him to marry he replied:
He divided tha year in 365 days according to Dioegenes Laertios who also has written that Thales died in the stadium looking some athletic game. When the visitors left they found that Thales remained there looking as sleeping. He was actually dead. Thales died in the 58th Olympiad period (548-545 BC)
According to Proclus to Thales we owe several propositions later included by Euclid in his Elements. Thales is probably the first Greek mathematician to demonstrate or prove that:
Lunar Crater Thales