Hicks: The wise man will also feel grief, according to Diogenes in the fifth book of his Epilecta.
Yonge: The wise man will be subject to grief, as Diogenes says, in the fifth book of his Select Opinions;
Original text: καὶ λυπηθήσεσθαι δὲ τὸν σοφόν, ὡς ὁ Διογένης ἐν τῇ πέμπτῃ τῶν Ἐπιλέκτων:
λυπηθήσεσθαι "to grieve about a thing" which makes sense in light of the sage being more susceptible to emotions but it not being a hindrance.