Task: Classify the mental state of the tweeter based on the tweet, determining if it is 'neutral or no emotion' or characterized by any of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
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