Task: Determine the appropriate intensity class for the tweet, reflecting the level of emotion E experienced by the user. 0: no E can be inferred. 1: low amount of E can be inferred. 2: moderate amount of E can be inferred. 3: high amount of E can be inferred.
Tweet: Paul Ehrlich said that humanity is a threat to all life. Such great news to start the day. If I could blush I would.
Emotion: sadness
Intensity class: 