Examine the tweet "Regret for the things we did can be tempered by time; it is regret for the things we did not do that is inconsolable.  Sydney J. Harris" and determine which of these emotions are present: anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust. If there are no identifiable emotions, reply with "neutral or no emotion".
optimism, sadness