But, happily for us, our evolution is determined not only by entropy, but also by the accumulation of knowledge and technological progress – a process that is just as irreversible as the decrease in stocks of non-renewable resources and the degradation of environmental quality. Thus, the economy is entropic for resources and historical for the production, organization, and spread of knowledge, with the prospects for economic and environmental sustainability residing in the space left between those two dynamic processes: the level of growth we choose must be conditioned on a sufficient level of knowledge to ensure the system’s survival.