Cunning leads to knavery. It is but a step from one to the other, and that very slippery. Only lying makes the difference; add that to cunning, and it is knavery.
When all the other animals, downcast looked upon the earth, he [Prometheus] gave a face raised on high to man, and commanded him to see the sky and raise his high eyes to the stars.
Take this at least, this last advice, my son:
Keep a stiff rein, and move but gently on:
The coursers of themselves will run too fast,
Your art must be to moderate their haste.