σκληρόψυχος
From LSJ
ὑπὸ δὲ τῆς φιλαυτίας παρηγμένοι ἄλογα φασὶν τὰ ζῷα ἐφεξῆς τὰ ἄλλα σύμπαντα → it is self-love which leads them to say that all the other animals without exception are non-rational
English (LSJ)
ον,
A hard-hearted, Sch.rec.A.Pr.242.
German (Pape)
[Seite 901] harthetzig, Schol. Aesch. Prom. 242.
Greek (Liddell-Scott)
σκληρόψῡχος: -ον, ὁ ἔχων σκληρὰν ψυχήν, σκληροκάρδιος, Σχόλ. εἰς Αἰσχύλ. Πρ. 242.