Well, I've read Confessions by St.Augustine and I'll be getting City of God either later this week or right after Christmas. I've also read both Immortale Dei and Libertas sevral times. And here is supposed to be a quick summary of the two of them. Not that I can make an extensive summary of them, not that I would try to make an extensive summary of them, not that any of you would read what I had written - well, you might, but it won't be anytime soon.
As a quick summary of Immortale Dei governments are destined to govern because that is there job. Governments should govern justly and fairly. If they don't the people governed have the right of selecting a different government.
It therefore seems likely that if a government wants to government many people that it would be a fair and just government. Because if the government were neither just nor fair, then people would get up and move. This could be as dramatic and changing cities or changing countries and languages.
Summarizing Libertas, people will and should be allowed to do whatever they choose - as long as it doesn't go against the will of God. However, not everyone is Catholic and we therefore get into the arguement of what should people be allowed to do that Catholic cannot, should not, or would not.
This leads to a fairly minimalist and fairly "hands off" of government. It also leads to other stipulations which I think I'll write about later.