The Tortoise and The Eagle

A Tortoise, discontented with his lowly life, and envious of the birds he saw disporting themselves in the air, begged an Eagle to teach him to fly. The Eagle protested that it was idle for him to try, as nature had not provided him with wings; but the Tortoise pressed him with entreaties and promises of treasure, insisting that it could only be a question of learning the craft of the air. So at length the Eagle consented to do the best he could for him, and picked him up in his talons. Soaring with him to a great height in the sky he then let him go, and the wretched Tortoise fell headlong and was dashed to pieces on a rock.

Envy or foolish ambition can lead to your own ruin.