The game of discontent has its rules, and he who disregards them cheats. It is not permitted to you to wish to add another's advantages or possessions to your own; you are permitted only to wish to be another.
That single thought is enough. The impulse increases to a wish, the wish to a desire, the desire to an uncontrollable longing, and the longing (to the deep regret and mortification of the speaker, and in defiance of all consequences,) is indulged.