XI. Progressive Development Through The Different Cycles Of Culture

You may gather from this that upon the Sun and upon the Moon the mineral kingdom was a vegetable kingdom. The vegetable kingdom has not developed out of the mineral kingdom, but minerals have developed out of the vegetable kingdom! The coal which is now dug out of the earth is nothing but a complex of petrified plant—plants which decayed and became stones, so that now they can be dug out of the earth as petrified plants. If you were to go back still further, you would see that once even the hardest stones were plants; and that they have arisen out of plants through the descending development of plants to the mineral kingdom.