Heal the mind, not the couch. Seneca, Epistles 2.17.11-12
Health requires us to change our minds, adapting them to our circumstances rather than the reverse. Seneca's counsel to Lucilius here reminds me of the poem by Rudyard Kipling: “If you can meet with Triumph and Disaster, and treat those two impostors just the same … yours is the Earth, and everything that's in it, and—which is more—you'll be a Man, my son!”
Poteram hoc loco epistulam claudere, nisi te male instituissem. Reges Parthos non potest quisquam salutare sine munere; tibi valedicere non licet gratis. Quid istic? ab Epicuro mutuum sumam: multis parasse divitias non finis miseriarum fuit sed mutatio. Nec hoc miror; non est enim in rebus vitium sed in ipso animo. Illud quod paupertatem nobis gravem fecerat et divitias graves fecit. Quemadmodum nihil refert utrum aegrum in ligneo lecto an in aureo colloces—quocumque illum transtuleris, morbum secum suum transferet—, sic nihil refert utrum aeger animus in divitiis an in paupertate ponatur: malum illum suum sequitur. Vale.
I could end this epistle here, but that would deprive you of your due. None can greet the Parthian kings without a gift; it is not right for me take leave of you without offering a contribution. What shall I provide? Another gem borrowed from Epicurus: “Many have found the acquisition of wealth to be not the end of their misery, but merely a change in its expression.” This does not surprise me! Vice is not a property of things, but of the mind itself. Whatever has made poverty hard for us to bear will make wealth onerous, too. As it makes no different to the grievously ill whether you place him on a wooden couch or a golden one—for he carries with him his illness, wherever you may place him—so it matters not whether you nurse a sick mind in wealth or in poverty. The mind's illness follows it everywhere. Farewell.