Fable 146 - The Camel and Zeus

The camel, seeing the bull have the advantage of horns, was envious of him and wanted to acquire some too. He went to find Zeus
and begged him to furnish him with some horns. But Zeus, angry that he was not content already with his great size and with his strength,
and wanted yet more, not only refused to add some horns but proceeded to cut off a portion of his ears.

So it is that many people, through greed, look upon others with envy, not realizing that they are losing their own advantages.