As we have already said, it is easy to put the seeds in the earth and wait till the plants grow out of it, but nobody can make all the things that are needed to make it work. No man can make earth and air, light and water, or the day and the night. It is exactly the same with all other things. For instance, man can build houses. He needs stones to do this, but he cannot make the stones himself.
Man can also build cars and aeroplanes.
To do this he also needs, among other things, iron and rubber. Again, he cannot make iron and rubber himself. Iron can be found in some rocks, and when these rocks are made hot, the iron turns to fluid and flows out of them. Rubber can be found in certain trees. When the bark of these trees is cut, liquid rubber juice flows out.