When I read anything on wikipedia, every subject and concept seem to have their roots in Ancient Greece. Mathematics and Euclide, medicine and Hippocrates, literature and Homer etc.
And then there is that fella called Aristotle. How can one person name so many essential concepts and be influential in so many fields? Like there have been millions of people before him.
Why Greece? It just boggles my mind that the foundations of so many basic concepts of culture and life have been laid in Ancient Greece.
More can always be said, but u/iphikrates provides some context for this claim in an answer to a similar question here:
https://www.reddit.com/r/AskHistorians/comments/r2urd2/athens_a_small_city_of_250k_gave_rise_to_a/
Note there's lots of good discussion in the comments too, including some dissent.
Also notice the question was focused on Athens - for most laymen Athens is basically synonymous with classical Greece (and Sparta thanks to THIS IS SPARTA). We know a lot more about Athens than any other Greek city-state, and it's been the focus of study for centuries now.
In fact iphikrates talks a bit about the focus on Athens here: https://www.reddit.com/r/AskHistorians/comments/yn0nd8/the_two_ancient_greek_cities_we_know_the_most/
Edit: you mention things like mathematics and literature. Certainly the Pythagorean theorem was known in ancient Mesopotamia and Egypt thousands of years before Pythagoras. The earliest known sumerian poems of Gilgamesh date to around 2000 BC. We associate these things with Greece not because they were first but for cultural and historical reasons.