Are these negative emotions (shame, envy, jealousy) adaptive? If so, who benefits, and how do they benefit? Are these emotions the result of primate hierarchies? What would it be like if these emotions did not exist? Are these emotions genetic or cultural, or can they be separated? What is the ultimate cause of these emotions? Why do females complain about males not showing their emotions? Why are robotics engineers teaching robots to have emotions (“human in the loop”—google search engine)? Are psychotherapists screwing up eugenics by treating people with these emotions? Is it deceptive to hide negative emotions? Is there an arms race between deception to hide negative emotions, and detection of this deception? Does negative emotions correlate with inferior genes (relative beauty, relative wealth)? Does social comparison cause negative emotions? Why do we compare and choose mates? Would it be a good idea if all our thoughts were detectable, and would this be ultimate honesty? Are negative emotions fitness indicators, if so, why am I so unfit? Why me and not you? Why are people reluctant to discuss this?
Emotions are not just experiential bon-bons. They are sensory input. You feel “negative” emotions in order to interpret them and understand your situation (usually, in the case of negative emotions, with an aim towards changing something that isn’t in your best interests).
Deprived of emotional input, you would be as if blinded or deafened, except significantly more so.
Context is everything. Shame serves as a guide to social acceptance which fosters cooperation and group cohesion. Envy and jealousy can prompt an individual to better his personal situation. One can argue that without such desires progress (both as individuals and as a species) would cease.
Absolute contentment is a wonderful thing to feel, but it doesn’t spur one to invent the wheel.