You can always quote Bertrand Russell:

“Envy consists in seeing things never in themselves, but only in their relations. If you desire glory, you may envy Napoleon, but Napoleon envied Caesar, Caesar envied Alexander, and Alexander, I daresay, envied Hercules, who never existed.”

What book is that from?

I don't know and a quick Google search doesn't give any sources either.

Nevermind: The quote seems to be from "The Conquest of Happiness: A Modern-Day Interpretation of a Self-Help Classic".

Feel free, I'm just glad my comments are well received enough to be quotable :)