Stages of civilization measured by scripts they use

My point here is that life has access to level of literacy that humans have yet to achieve, and may never achieve. We enjoy our current prosperity with too much confidence that it will last forever. We have no permanent record of how we got this to work. Once we collapse, our predecessors may never be able to anything more than scavenge through our ruins. They would be as likely to rediscover how to make megalithic monuments as to rediscover how to create modern life, and that likelihood is near zero.