@j126: Here's the full version of your quotation*, attributed to Thales (Plutarch, "Symposium of the Seven Sages," Moralia 1.153d), in the original ancient Greek:
Τί κοινότατον; ἐλπίς. καὶ γὰρ οἷς ἄλλο μηδέν, αὕτη πάρεστι.
— "What is most common? Hope. For those who have nothing else, that is always there."
*Ti koinotaton? Elpis. Kai gar hois allo meden, haute paresti.