You are far from civilization. It’s pointless to ask why or how you got here. Like Crusoe, you must survive. Perhaps you have a few fellow shipwrecks along with you, your family or chosen friends. If not, the island is yours alone. You rescued some supplies from the ship before it broke apart on the shoals. You have these saving vestiges of the civilized world.  An axe, some saws and knives; a musket and ammunition; a hogshead of stale bread – these things and a few more. A lifetime stretches before you. Never have you felt so puny. Never have you examined the horizon or viewed the waves upon a beach with such hostility and incomprehension. Take a walk. Pummel the sand. Pull your hair and weep. Then put aside your rebellion.  You are alive.  Assuming that a bare subsistence can be had from this island, what is it you most need? Make a list. 1.  Your sanity.  The area of a circle is pi times the radius squared. The fourth president of the United States was James Madison. The longest river in the world is the Nile. You see. Your mind works. This is not genius. This is sense. One thought proceeds from another. There is a cosmos within, orderly and rational, at your beck and call. 2.  Your hands.  They seemed as quaint as spinning wheels and covered wagons. Now you know the truth. You can plant barley, skin a goat,…