 The most basic purpose of a civilization is to propagate itself, not the only purpose, but one of the most basic, just as the most basic biological purpose of each individual human is to reproduce. So it follows that a civilization which gives up on producing humans will inevitably collapse. And that's why I am worried about the trend in the West towards childlessness and childishness, I guess. As our fertility rate drops below replacement level, we more and more resemble a society that has basically given up on itself.