This is a great video, it's a little long and you may think it's all obvious, but I really think it is worth watching for people who are curious or unsure about what liberty actually is when broken down to it's smallest components. http://www.youtube.com/watch?v=muHg86Mys7I There is another great video out there that explains Problem => Reaction => Solution, which I also thinks is great viewing, but I can't find it right now.