Joy is serious business. Seneca, Epistles 3.23.4-5

Seek the joy that lies deep in the moments your life already has. Be patient enough to notice how you are already very blessed, in some way that only you can appreciate—some way that cannot be published or envied or broadcast to the world at large.

Mihi crede, verum gaudium res severa est. An tu existimas quemquam soluto vultu et, ut isti delicati loquuntur, hilariculo mortem contemnere, paupertati domum aperire, voluptates tenere sub freno, meditari dolorum patientiam? Haec qui apud se versat in magno gaudio est, sed parum blando. In huius gaudii possessione esse te volo: numquam deficiet, cum semel unde petatur inveneris. Levium metallorum fructus in summo est: illa opulentissima sunt quorum in alto latet vena assidue plenius responsura fodienti. Haec quibus delectatur vulgus tenuem habent ac perfusoriam voluptatem, et quodcumque invecticium gaudium est fundamento caret: hoc de quo loquor, ad quod te conor perducere, solidum est et quod plus pateat introrsus.

True joy is serious business, believe me. Despising death, opening your home to poverty, holding pleasures at bay, studying patience under duress: do these strike you as likely pastimes for every fool with a face free and fresh, as the dandies say? The man who handles them intimately dwells in great rejoicing, but not the kind that attracts admirers. I want you to be in possession of his joy: once you have discovered where to seek it, it will never leave you lacking. The ore that remains in well-scoured mines lies in the depths: the biggest strikes occur when some persistent miner discovers a vein hidden deep, lying in wait to reward his patience. But the crowd delights in things that bestow pleasure too slight and superficial for patience, and whatever joy they take is accordingly insincere and unstable, lacking any sure foundation. The joy I am talking about, to which I am attempting to lead you, is something solid and substantial, though it cannot easily leave the confines of the mind.