"The fox knows many things, but the hedgehog knows one big thing," the Greek poet Archilochus said in the 8th century B.C.

This ancient notion came up in Croesus' interview with George Soros this week when he extolled his late friend Leon Levy, an astute billionaire investor, as a hedgehog who knew for sure when markets were overvalued and stuck to his guns; while he, Soros, was a fox who knew many things and was more impatient in the marketplace.