A video from California Institute of Technology about how early ancient Greek mathematicians built the tunnel of Samos which exists until today and why it is still relavent to modern engineering.
"Philo" in Ancient Greeks means Love
"Xenia" in Ancient Greeks means Stranger
So, Philoxenia literally means Love of the stranger
We still use the same word (Philoxenia) for hospitality.
How an ancient Greek mathematician could measure the earth's circumference 2200 years ago?
The resemblance of ancient Greek (2600 years ago) with modern Greek language is very big. The language that Socrates taught his students and Plato taught in the Academia is very much resembling our modern Greek. Moreover, M. Ventris very recently (1952) discovered the resemblance of linear Mycenaean language with the Ancient Greek Language.