Define civilization. Do we really need it in order to survive and prosper on this planet? The real question is whether we can live above subsistence without the technological innovations that cities generate. Moreover, the question is not as frivolous as it may seem at first glance. Many cultures throughout human history consciously decided not to take the route toward nucleated settlements and the resultant consequences. The Celts represent one example from the time line of our course of a people who preferred not to have cities. The Avars, a Turkic-speaking people from Central Asia, were pastoral nomads who acquired cities during the course of their conquests, yet they "used" cities in ways that would strike average city dwellers as most strange.