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: #Pain is an aspect of #human evolution; the evolution of #consciousness. #attachments #desire #apathy #sentimentality #tears   #O
This tweet contains emotions: 
anticipation, fear, sadness