The easiest thing in the world is self-deceit; for every man believes what he wishes, though the reality is often different.
ῥᾷστον ἁπάντων ἐστὶν αὑτὸν ἐξαπατῆσαι· ὃ γὰρ βούλεται, τοῦθ᾿ ἕκαστος καὶ οἴεται, τὰ δὲ πράγματα πολλάκις οὐχ οὕτω πέφυκεν.
Original text (Ancient Greek)
Notes from Wikiquote
A man is his own easiest dupe, for what he wishes to be true he generally believes to be true. | Compare Caesar, Gallic War, III.18:
fere libenter homines id quod volunt credunt.
People readily believe in something they want. (tr. C. Damon, 2025)
Variants
(R. Andrews, 1987)