Task: Analyze the tweet's emotional connotations and classify 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 best portray the tweeter's mental state.
Tweet: “The #greatest fear #dogs know is the #fear that you will not come back when you go out the #door #without them.”   \n  ―#Stanley #Coren
This tweet contains emotions: 
fear