Task: Assess the emotional content of the tweet and classify it as either 'neutral or no emotion' or as one or more of the given emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that best represent the tweeter's mental state.
Tweet: The man who is a pessimist before 48 knows too much; if he is an optimist after it, he knows too little.'\n-Mark Twain
This tweet contains emotions: 
optimism, pessimism, trust