I'm totally with you on that, it's a very interesting point and the notion of what a civilization is or how the people being part of it interact together is fascinating! I don't know if you are familiar with Isaac Asimov's books but he tackled the issue of civilizations and how the interactions inside of them would be completly different from what we know. For your definition, I have a question which is more philosophical than anything else. Do the members have to be aware that they're sharing a common goal and structure? Or is it something defined by an outsider or later in time when you have some insight about that said civilization? Good job!