“Let your speech not be false, and your deeds not be unjust.”
— Thales of MiletusCommonly cited moral maxim in anthologies attributed to Thales; approximate English rendering, source not confirmed

Commentary

This maxim, attributed to Thales in later anthologies, joins a prohibition on falsehood to a prohibition on injustice, presenting honesty of speech and rectitude of action as two aspects of the same moral integrity. The pairing reflects a common Greek ideal of congruence between word and deed. A. A. Long notes that the moral sayings of the sages were often composed in parallel forms, and that this maxim follows that pattern. G. S. Kirk, J. E. Raven, and M. Schofield observe that such maxims are not securely attributable to Thales, since they appear in collections compiled long after his lifetime. Charles Kahn suggests that the moral concerns expressed here reflect the civic conditions of Ionian cities. Jonathan Barnes cautions that the maxim should be labelled a traditional attribution. The English is an approximation of a Greek formula, and the attribution should not be presented as verified.