empathy is a important part in human interaction, and imitation is part of it, but as well I am convinced that things like envy come from education and the society we live in...think about native tribes, for example they tend not to have posession of material things, if I don´t need it anymore another one can have it..no envy necessary....the envy in our society is a big problem...but it´s not instinctively, a destructive thing can´t be in the core of our feelings I believe, because it would have held humans back from evolution