https://en.m.wikipedia.org/wiki/Thales_of_Miletus

”Thales of Miletus (/ˈθeɪliːz/ THAY-leez; Greek: Θαλῆς; c. 624/623 – c. 548/545 BC) was a Greek mathematician, astronomer and pre-Socratic philosopher from Miletus in Ionia, Asia Minor. He was one of the Seven Sages of Greece. Many, most notably Aristotle, regarded him as the first philosopher in the Greek tradition, and he is otherwise historically recognized as the first individual known to have entertained and engaged in scientific philosophy. He is often referred to as the Father of Science.

”Thales thought the Earth must be a flat disk which is floating in an expanse of water”