What is left is 1/4. Slice it in half. Set aside one of the halves. This is the part of the Earth on which people cannot live, the poles, deserts, swamps and high mountains.
What is left is 1/8. This is where the humans live, but not necessarily where they grow their food.
Slice your 1/8 piece into four sections. Put aside three of them. What is left is 1/32. The three pieces you set aside represent the places where the soil is too poor to farm--too rocky, wet, cold or steep. These also represent the cities, homes, highways, shopping malls, schools, parks, factories, parking lots and golf courses where people live play and work--but do not grow food.
Take the 1/32 piece that remains. Carefully peel it. Look at this tiny scrap of apple peel. This represents the surface topsoil of the planet that may be farmed. This thin skin represents the thin skin on the Earth's crust upon which humankind totally depends. This soil is less than 5 feet deep and is a fixed amount of food-producing land.
Eat the rest of your apple, but save that tiny piece of apple skin. Treat is as if your life depends on it.
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