The ex libris of Freud's library featured an image of Oedipus in front of the Sphinx. Between the two figures is apparent in Greek lettering that shows the direction of 1585 Oedipus Rex by Sophocles:
"ὄς τὰ κλείν᾽αἰνίγματ᾽ᾔδει καὶ ἦν κράτιστος ανήρ"
"Behold who solved the enigma and was the most powerful among men".
