Moral Letters to Lucilius Section 24

Quoniam hac similitudine usus sum, perseverabo: animus noster modo rex est, modo tyrannus. Rex, cum honesta intuetur, salutem commissi sibi corporis curat, et illi nihil imperat turpe, nihil sordidum. Ubi vero inpotens, cupidus, delicatus est, transit in nomen detestabile ac dirum et fit tyrannus; tunc illum excipiunt adfectus inpotentes et instant, qui initio quidem gaudent, ut solet populus largitione nocitura frustra plenus, et quae non potest haurire, contrectat.

notre âme est tantôt roi, tantôt tyran :

To persist in my use of this simile - our soul is at one time a king, at another a tyrant. The king, in that he respects things honourable, watches over the welfare of the body which is entrusted to his charge, and gives that body no base, no ignoble commands. But an uncontrolled, passionate, and effeminate soul changes kingship into that most dread and detestable quality - tyranny; then it becomes a prey to the uncontrolled emotions, which dog its steps, elated at first, to be sure, like a populace idly sated with a largess which will ultimately be its undoing, and spoiling what it cannot consume.