“When you strike off on your own, leave some trace of your passage which will guide you coming back: one stone set on another, some grass weighted by a stick. But if you come to an impasse or a dangerous spot, remember that the trail you have left could lead people coming after you into trouble. So go back along your trail and obliterate any traces you have left. This applies to anyone who wishes to leave some mark of his passage in the world. Even without wanting to, you always leave a few traces. Be ready to answer to your fellow men for the trail you leave behind you.”