Laudator Temporis Acti

Aristotle, Politics 7.6.1327a (tr. H. Rackham):

As to communication with the sea it is in fact much debated whether it is advantageous to well-ordered states or harmful. It is maintained that the visits of persons brought up under other institutions are detrimental to law and order, and so also is a swollen population, which grows out of sending out abroad and receiving in a number of traders, but is unfavorable to good government.

περὶ δὲ τῆς πρὸς τὴν θάλατταν κοινωνίας, πότερον ὠφέλιμος ταῖς εὐνομουμέναις πόλεσιν ἢ βλαβερά, πολλὰ τυγχάνουσιν ἀμφισβητοῦντες· τό τε γὰρ ἐπιξενοῦσθαί τινας ἐν ἄλλοις τεθραμμένους νόμοις ἀσύμφορον εἶναί φασι πρὸς τὴν εὐνομίαν, καὶ τὴν πολυανθρωπίαν· γίνεσθαι μὲν γὰρ ἐκ τοῦ χρῆσθαι τῇ θαλάττῃ διαπέμποντας καὶ δεχομένους ἐμπόρων πλῆθος, ὑπεναντίαν δ᾽ εἶναι πρὸς τὸ πολιτεύεσθαι καλῶς.

W.L. Newman ad loc.:

That contact with aliens might have ill results, we see from Cic. De Leg. Agrar. 2.35.95, Carthaginienses fraudulenti et mendaces non genere, sed natura loci, quod propter portus suos multis et variis mercatorum et advenarum sermonibus ad studium fallendi studio quaestus vocabantur. Contact with aliens even of a satisfactory type might well affect the fidelity of the citizens of a Greek State to its traditions, and many of the aliens who crowded to Greek seaports were Asiatics of a type the reverse of satisfactory.