The Mayan calendar is based on the idea of cycles and cycles within cycles. This is not too different than either the Ptolemaic system or even the modern view of a moon that revolves around a planet that revolves around a Sun that in turn revolves around the center of a galaxy.
At some point though we discard the notion of cycles when it comes to human progress. Although we like to play with ideas of a post-nuclear world where civilization must rebuild itself, the prevailing view is that progress is linear, that life and civilization will expand and grow until it dominates not only other solar systems but also the entire universe.
This attitude is embodied in such theories as Frank Tipler's idea of an Omega point or among the futuristic theories of Nick Bostrom and his fellow transhumanists. The essential idea is that the future is limitless and that scientific progress, now that it has fully developed its young wings and survived the peril of being quashed by other dogmas, is poised for flight.
Once you accept the idea that we will continue to grow and develop until we are well past the point of being superhuman you can make all sorts of deductions. Tipler's Omega point theory relies on the idea that we will be able to control the universe and harness its seemingly limitless computing power. What will we do with all this power? Why we will of course use it to reconstruct simulations of our own past! Including, of course, this past, the world we live in now, inhabited by you and me and all of our loved ones and even our not so-loved ones. Also, hopefully, our pets. This is our immortality. We will be brought back to life, reconstituted by our super-powerful descendants, like a can of dried milk.
As outrageous as that may seem, Bostrom goes even further. He argues essentially that our descendants will not just construct one simulation, but countless numbers of them. After all, they live in an infinite future, harnessing the power of universes. Why shouldn't they build not just one Napoleonic War but also re-run it endlessly, as we re-run films, creating us in each viewing.
The outrageous and inevitable conclusion is this: If there are so many simulations and only one authentic version, well, what really are the chances that we are that authentic version? Bostrom argues that it is much more likely that we are a copy, that we are a mere simulation, and so he urges us to accept that.
The Mayans, as I was saying earlier, held, in contrast, that it is cycles all the way up. The universe will end. We will end. Everything will begin again. This may even happen as soon as 2012.
At this point it is not clear to me which view of the world makes more sense.