Task: Categorize the tweet's emotional tone as either 'neutral or no emotion' or identify the presence of one or more of the given emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
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