Seneca, Moral Epistle 98.1-2

“You don’t ever need to believe that anyone who relies on happiness is really happy. Whoever delights in things outside of their control leans on brittle supports: external happiness will go away. But the feeling that rises from oneself is legit and strong–it grows and stays with us to our final moment. Everything else that has common esteem is good for like a day.

So, in response, “Huh? What’s this? Can’t things serve for both function and pleasure?” Who denies that? But only if they need us, not if we need them. All things governed by fortune can be profitable and pleasing if the person who has them also controls themselves and is not under the power of the things they own.

People screw up, Lucilius, when they judge anything fortune gives them as something good or evil. Luck grants us the foundations for good or evil and the sources of good and evil affairs among us. The spirit is stronger than all fortune and directs its own affairs on either path–it is the reason we have a happy life or a miserable one.”

Numquam credidcris felicem quemquam ex felicitate suspensum. Fragilibus innititur, qui adventicio laetus est; exibit gaudium, quod intravit. At illud ex se ortum fidele firmumque est et crescit et ad extremum usque prosequitur; cetera, quorum admiratio est vulgo, in diem bona sunt. “Quid ergo? Non usui ac voluptati esse possunt?” Quis negat? Sed ita, si illa ex nobis pendent, non ex illis nos.

Omnia, quae fortuna intuetur, ita fructifera ac iucunda fiunt, si qui habet illa, se quoque habet nec in rerum suarum potestate est. Errant enim, Lucili, qui aut boni aliquid nobis aut malum iudicant tribuere fortunam; materiam dat bonorum ac malorum et initia rerum apud nos in malum bonumve exiturarum. Valentior enim omni fortuna animus est et in utramque partem ipse res suas ducit beataeque ac miserae vitae sibi causa est.