This paper will argue that the global capitalist economy was founded, and depends, on the consumption of fossil fuels, and the increase in supply of renewable energy in the next three decades will not alter that fact significantly, given both economic and demographic growth and Jevons’ Paradox. The resulting increase in fossil fuel consumption in that time, along with that increased economic activity and human population, which is already unsustainable, will lead to increased greenhouse gas (GHG) emissions, further anthropogenic climate change, and loss of biodiversity. The so-called ‘Doomsday Argument’ predicts that the deleterious impacts of these effects will be so severe as to result in the extinction of our entire species.