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: @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