Task: Assess the emotional content of the tweet and classify 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 best represent the tweeter's mental state.
Tweet: @Mysteri759 @Ren102e906 @slb42jcb @swoozyqyah Well, I'm too old, and too stubborn about facts &amp; history to be discouraged.
This tweet contains emotions: 
anger, pessimism, sadness