From Diogenes Laertius’ Lives of the Eminent Philosophers 1.85-86
“To become strong is nature’s work. To be able to speak advantages for one’s country is the province of the soul and thought. Fate may bring great wealth to many. He used to say that it is unfortunate to not be able to endure misfortune. It is a sickness of the soul to love the impossible. We must not obsess over another’s troubles. When asked what is difficult, he said “nobly enduring change for the worse.” While he was sailing with some irreverent men, it started to storm. As they were calling upon the gods, he said “be quiet—you don’t want them to know you’re sailing.” When an unholy man asked him what was sacred, he was silent. When the same man asked him the cause of his silence, he said “I am silent because you ask about things that have nothing to do with you.”
When someone asked what is sweet for men, he said “hope”. He used to say that it was sweeter to judge between enemies than friends. For one of the friends will become your enemy after but one of your enemies will become a friend. When asked what a person delights doing, he said “making money”.
He used to advise us to measure life as if we had both a lot and a little time. And to love people as if they might some day hate them, since most people are bad. He also counselled this: approach deeds slowly, but once you begin an action, pursue it seriously. Don’t chatter quickly: for this marks insanity. Love wisdom. Speak of the gods that they exist. Don’t praise a worthless man because of wealth. Obtain what you want by persuasion not force. Whatever good you accomplish, credit the gods. Take wisdom as your guide from youth to old age: it is more certain than any other possession.”
 καὶ τὸ μὲν ἰσχυρὸν γενέσθαι τῆς φύσεως ἔργον: τὸ δὲ λέγειν δύνασθαι τὰ συμφέροντα τῇ πατρίδι ψυχῆς ἴδιον καὶ φρονήσεως. εὐπορίαν δὲ χρημάτων πολλοῖς καὶ διὰ τύχην περιγίνεσθαι. ἔλεγε δὲ ἀτυχῆ εἶναι τὸν ἀτυχίαν μὴ φέροντα: καὶ νόσον ψυχῆς τὸ τῶν ἀδυνάτων ἐρᾶν, ἀλλοτρίων δὲ κακῶν ἀμνημόνευτον εἶναι. ἐρωτηθεὶς τί δυσχερές, τὴν “ἐπὶ τὸ χεῖρον,” ἔφη, “μεταβολὴν εὐγενῶς ἐνεγκεῖν.” συμπλέων ποτὲ ἀσεβέσι, χειμαζομένης τῆς νεὼς κἀκείνων τοὺς θεοὺς ἐπικαλουμένων, “σιγᾶτε,” ἔφη, “μὴ αἴσθωνται ὑμᾶς ἐνθάδε πλέοντας.” ἐρωτηθεὶς ὑπὸ ἀσεβοῦς ἀνθρώπου τί ποτέ ἐστιν εὐσέβεια, ἐσίγα. τοῦ δὲ τὴν αἰτίαν τῆς σιγῆς πυθομένου, “σιωπῶ,” ἔφη, “ὅτι περὶ τῶν οὐδέν σοι προσηκόντων πυνθάνῃ.”
6  Ἐρωτηθεὶς τί γλυκὺ ἀνθρώποις, “ἐλπίς,” ἔφη. ἥδιον ἔλεγε δικάζειν μεταξὺ ἐχθρῶν ἢ φίλων: τῶν μὲν γὰρ φίλων πάντως ἐχθρὸν ἔσεσθαι τὸν ἕτερον, τῶν δὲ ἐχθρῶν τὸν ἕτερον φίλον. ἐρωτηθεὶς τί ποιῶν ἄνθρωπος τέρπεται, ἔφη, “κερδαίνων.”
ἔλεγέ τε τὸν βίον οὕτω μετρεῖν ὡς καὶ πολὺν καὶ ὀλίγον χρόνον βιωσομένους, καὶ φιλεῖν ὡς μισήσοντας: τοὺς γὰρ πλείστους εἶναι κακούς. συνεβούλευέ τε ὧδε: βραδέως ἐγχείρει τοῖς πραττομένοις: ὃ δ᾽ ἂν ἕλῃ, βεβαίως τηρῶν διάμενε. μὴ ταχὺ λάλει: μανίαν γὰρ ἐμφαίνει. φρόνησιν ἀγάπα. περὶ θεῶν λέγε, ὡς εἰσίν. ἀνάξιον ἄνδρα μὴ ἐπαίνει διὰ πλοῦτον. πείσας λαβέ, μὴ βιασάμενος. ὅ τι ἂν ἀγαθὸν πράττῃς, εἰς θεοὺς ἀνάπεμπε. ἐφόδιον ἀπὸ νεότητος εἰς γῆρας ἀναλάμβανε σοφίαν: βεβαιότερον γὰρ τοῦτο τῶν ἄλλων κτημάτων.