Task: Determine the prevailing emotional tone of the tweet, categorizing 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 most accurately represent the tweeter's mental state.
Tweet: Yesterday is history, tomorrow is amystery, and today is a gift; that's why they call it the present #livelife #humbleness  #live
This tweet contains emotions: 
joy, optimism