XI. Who are the Rosicrucians?

Consider for a moment the process of human breathing. The regulation of the breath is connected with the discovery, or preparation of, the philosopher's stone. At present human beings inhale oxygen and exhale carbon dioxide, that is, what is exhaled is a compound of oxygen and carbon. A person inhales oxygen, life-giving air, and exhales carbon dioxide, which is poisonous to both human and animal. If animals, who breathe like human beings, had alone populated the earth, they would have poisoned the air, and neither they nor humans would be able to breathe today. So how does it come about that they are still able to breathe? It is because plants absorb the carbon dioxide, retain the carbon and give back the oxygen for human and animal to use again.