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: Difficulties, by bracing the mind to overcome them, assist cheerfulness, as exercise assists digestion.\nChristian Nestell Bovee #quotes
This tweet contains emotions: 
joy, optimism