Our civilization must slow down so that we can learn to use progress responsibly. In other words, the entire world must agree to a one-child policy for two or three generations — that is, we must agree to limit our family size to one child only — resulting in a smaller world population. This reduced population will have a small carbon footprint, which means we will have more time to convert to climate-friendly green energy (solar, wind, electric). Then when we begin to behave responsibly as a species, we can resume population growth.