[22] And again, it will also not be dissolved by any cause existing within itself; first of all because, if it were, then the part would be greater and more powerful than the whole, which is the greatest possible absurdity, for the world, enjoying an unsurpassable power, influences all its parts, and is not itself influenced or moved by any one of them; in the second place because, since there are two causes of corruption, the one being internal and the other external, those things which are competent to admit the one must also by all means be liable to the other;