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: At my age all I see is gray. Is it gray because of my bad eyes or my perspective #depression  #healingjustice
This tweet contains emotions: 
sadness