Known sourcecanonical
"It was a saying of Demetrius Phalereus, that "Men having often abandoned what was visible for the sake of what was uncertain, have not got what they expected, and have lost what they had,--being unfortunate by an enigmatical sort of calamity.""
Athenæus / The Deipnosophists. vi. 23.
The Deipnosophists. vi. 23.
Bartlett's Familiar Quotations, 9th ed. (Little, Brown, 1905), public domain