καὶ καθ' ὅσον ἀπόκειται τοῖς ἀνθρώποις ἅπαξ ἀποθανεῖν

From LSJ

ἀλώπηξ, αἰετοῦ ἅ τ' ἀναπιτναμένα ῥόμβον ἴσχει → a fox, which, by spreading itself out, wards off the eagle's swoop

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