Task: Categorize the tweet's emotional expression, classifying it as either 'neutral or no emotion' or as one or more of the specified emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that reflect the tweeter's state of mind.
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