Etenim, iudices, cum omnibus virtutibus me adfectum esse cupio, tum nihil est quod malim quam me et esse gratum et videri. Haec enim est una virtus non solum maxima sed etiam mater virtutum omnium reliquarum.

In truth, O judges, while I wish to be adorned with every virtue, yet there is nothing which I can esteem more highly than being and appearing grateful. For this one virtue is not only the greatest but is also the parent of all the other virtues.

Pro Plancio (54 B.C.)