Have you never thought how danger must surround power as shadow does light? — Ursula K. Le Guin

From that time forth he believed that the wise man is one who never sets himself apart from other living things, whether they have speech or not, and in later years he strove long to learn what can be learned, in silence, from the eyes of animals, the flight of birds, the great slow gestures of trees.

It is light that defeats the dark.

You must not change one thing, one pebble, one grain of sand, until you know what good and evil will follow on that act. The world is in balance, in Equilibrium. A wizard's power of Changing and Summoning can shake the balance of the world. It is dangerous, that power. It is most perilous. It must follow knowledge, and serve need. To light a candle is to cast a shadow.