I Have been arguing earlier with some friends whether the tendency of comparing oneself with others is natural or acquired.
Taking into account that some people never put themselves or lives into comparison with others. I believe it is a habit people acquire due to the way they have been raised. As most parents often excessively use comparison to motivate or punish their children, or by declaring how some of them is special and worthy of more care, and love because he is more successful, both their more and less successful children acquire that habit of comparison to identify how worthy they are.
So well put. I just want to add the thought that it is probably rooted much deeper than just that. I mean even the fact that Western morality has the concept of bad - no Eastern or Oriental philosophy thought of such a ridiculous idea as the idea of "sin" - implies comparison.
This might be a great thing for scientists to study and research! I have always thought that it could be a natural tendency thanks to the evolutionary process, but one can't be too sure.