If we keep increasing energy consumption then it is possible that we could make ourselves extinct. There was an article in the New Scientist about the WBE equation ( <a href="http://en.wikipedia.org/wiki/Metabolic_theory_of_ecology" rel="nofollow">http://en.wikipedia.org/wiki/Metabolic_theory_of_ecology</a> ). Essentially, increased energy consumption increases lifespan and delays lifestyle choices but doesn't increase fertility. An example is that the birth rate of industrialised countries is vastly lower than unindustrialised countries. In North America, it has reached a situation where the population doesn't sustain itself. In parts of Europe where the population is not sustaining, some governments offer financial incentives in a futile attempt to fix the situation.<p>Shell geologist, M King Hubbert's originial 1956 paper on peak oil ( <a href="http://www.hubbertpeak.com/hubbert/1956/1956.pdf" rel="nofollow">http://www.hubbertpeak.com/hubbert/1956/1956.pdf</a> ) foresaw a bootstrap from fossil fuel to uranium reactors to thorium breeder reactors. However, it doesn't offer any help regarding energy consumption per head or the dissipation of that energy.