One may see hearts of different qualities: there is a golden heart, a silver heart, a copper heart and there is an iron heart.

• The golden heart shows its color and its beauty; it is precious and at the same time it is soft.
• The silver heart shows itself inferior compared to the golden heart; yet it is of silver that the current coins are made, so it is useful.
• There is the heart of copper of which pennies are made, and pennies are useful in everyday life; one has to use them more than gold and silver. Copper is hard and strong; it needs many hammerings to bend and shape it, to make something out of it.
• And then there is the iron heart which must be put into the fire before one can do anything with it. When in the glowing fire the iron has become hot then one can make something out of it. But how long does the heat of the fire last with it? A very short time! The blacksmith must be always ready; as soon as the fire begins to glow he must make something of it, for if he lets the moment go the iron will turn cold.
• Besides these different aspects there is a heart of rock, and there is a heart of wax. The heart of rock must be broken, it must be cut in order to make something out of it; nothing reaches it, cold or heat, sun or water have little effect upon it.
• The heart of wax melts as soon as it is heated. You can shape it without breaking it; it is soft, you can turn it any way you like.
• There is also the heart of paper you make a kite with. It flies and goes up; if the wind is in the north it goes to the north, if the wind is in the south it goes to the south. You can control it as long as the wind does not blow it out of your hands and as long as the wind is strong enough to hold it in the sky. But when there is no more wind it will drop down, and so you will try it again-like a kite.