Letters 95.54

Next, after considering gods and men, let us see how we should make use of things. It is useless for us to have mouthed out precepts, unless we begin by reflecting what opinion we ought to hold concerning everything—concerning poverty, riches, renown, disgrace, citizenship, exile. Let us banish rumour and set a value upon each thing, asking what it is and not what it is called.

Seneca, Letters to Lucilius 95.54, translated by Richard Mott Gummere