Nature helps us understand the principles of the life. There is no day without night. If there isn't light, we can't understand what darkness is, so everything contains the germ of destructiveness. In the stability, there is the germ of revolt. In the life, there is the germ of death. In short, the dual division is the evident truth of the life. Right and wrong, lives and death, happy and suffering.. Nothing is eternal. Nothing is changeless. Nothing is stable.