Euchesthai

Ὁκόσα μὲν οὖν τῶν ἐνυπνίων θεῖά ἐστι καὶ προσημαίνει ἢ πόλεσι ἢ ἰδιώτῃσι ἢ κακὰ ἢ ἀγαθὰ †μὴ δι’ αὐτῶν ἁμαρτίην,† εἰσὶ οἳ κρίνουσι περὶ τῶν τοιούτων τέχνην ἔχοντες· ὁκόσα δὲ ἡ ψυχὴ τοῦ σώματος παθήματα προσημαίνει, πλησμονῆς ἢ κενώσιος ὑπερβολὴν τῶν συμφυτῶν, ἢ μεταβολὴν τῶν ἀηθέων, κρίνουσι μὲν καὶ ταῦτα, καὶ τὰ μὲν τυγχάνουσι, τὰ δὲ ἁμαρτάνουσι, καὶ οὐδέτερα τούτων γινώσκουσι, δι’ ὅ τι γίνεται, οὔθ’ ὅ τι ἂν ἐπιτύχωσιν, οὔθ’ ὅ τι ἂν ἁμάρτωσι, φυλάσσεσθαι δὲ παραινέοντες μή τι κακὸν λάβῃ. οἱ δ’ οὖν οὐ διδάσκουσιν ὡς χρὴ φυλάξασθαι, ἀλλὰ θεοῖσιν εὔχεσθαι κελεύουσι. καὶ τὸ μὲν εὔχεσθαι ἀγαθόν· δεῖ δὲ καὶ αὐτὸν συλλαμβάνοντα τοὺς θεοὺς ἐπικαλεῖσθαι.
(Hippocrates, Peri Diaitēs 4.2)

Now such dreams as are divine, and foretell to cities or to private persons things evil or things good, have interpreters in those who possess the art of dealing with such things. But all the physical symptoms foretold by the soul, excess, of surfeit or of depletion, of things natural, or change to unaccustomed things, these also the diviners interpret, sometimes with, sometimes without success. But in neither case do they know the cause, either of their success or of their failure. They recommend precautions to be taken to prevent harm, yet they give no instruction how to take precautions, but only recommend prayers to the gods. Prayer indeed is good, but while calling on the gods a man should himself lend a hand. (tr. William Henry Samuel Jones)