Libanios, Oration 30, "For the Temples"

"It seems to me that one of the most pleasing things in cities, and one of the most useful, is meetings and mixings with other people.  We [citizens of Antioch] too have done honor to foreigners in the greatest of things, and have profited from foreigners, so that even now their families hold positions among the first.  Indeed, if a man had the idea of traveling all over earth with a concern not to see how the cities looked but to learn their individual ways, Antioch would fulfill his purpose and save him journeying.  If he sits in our market-place, he will sample every city; there will be so many people from each place with whom he can talk"