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: @TweeriaLee A stumbling block to the pessimist is a stepping stone to the optimist.
This tweet contains emotions: 
optimism