Proust

The excerpt, the Proust, incorporates the theme of how the same situation will never have the same outcome of emotions. This theme is explained through a depressed man who drinks tea for the first time. For “[no] sooner had the warm liquid … touched my palate than a shudder ran through me and I stopped, intent upon the extraordinary thing that was happening to me … at once the vicissitudes of life had become indifferent to me, its disasters innocuous, its brevity illusory - this new sensation having had on me the effect which love has of filling me with a precious essence; or rather this essence was not in me it was me” (1). This experience is often felt in many humans upon trying anything new or even remotely different from their daily routine. The emotions often exhibited when doing anything for the first time are often hard to replicate because you have already experienced it. But also, the key to being able to enjoy any situation whether it's repetitive or new is internally based. The depressed man wonders if this happiness can be replicated saying “What did [this all-powerful joy] mean? How could I seize and apprehend it? I drink a second mouthful, in which I find nothing more than in the first, then a third, which gives me rather less than the second. It is time to stop; the potion is losing it magic. It is plain that the truth I am seeking lies not in the cup but in myself” (1).  His ‘final enlightenment’ the depressed man knows that the happiness came from within himself. He immediately tries to recreate the memory which has long passed. The only issue with a task of this size is his emotions were true in the moment. The emotions he is trying to recreate are not ‘true’ and due to their lack of truth he fails at his task. It was only when the depressed man assumes his natural state that “suddenly the memory revealed itself … And as soon as i had recognized the taste… immediately the” memory and emotions flooded back to him revealing the happiness he once felt at that time while drinking from his “cup of tea” (2).

Proust, M. (1913-27). Remembrance of Things Past. Volume 1: Swann's Way: Within a Budding Grove. 
The definitive French Pleiade edition translated by C.K. Scott Moncrieff and Terence Kilmartin. New York: Vintage. pp. 48-51.