Task: Identify the primary emotion conveyed in the tweet and assign it to either 'neutral or no emotion' or one or more of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that best capture the tweeter's mental state.
Tweet: Even death is unreliable. Instead of zero it may be some ghastly hallucination, such as the square root of minus one.  Samuel Beckett
This tweet contains emotions: 
disgust, fear, pessimism, sadness