It turns out, however, that what most environmentalists know about the future supply of natural gas and other fossil fuels is based more on industry hype than on actual data. And, that means that they are missing a key argument in their discussions about renewable energy, one that could be used to persuade those less concerned about pollution and climate change and more concerned about energy security: There is increasing evidence that no fossil fuel will continue to see its rate of production climb significantly in the decades ahead and so none of them is a viable "bridge fuel," not natural gas, not oil, not coal. This means that global society must leap over fossil fuels and move directly to renewables as quickly as possible. In advanced economies this leap must be combined with a program of radical reductions in energy use, reductions which are achievable using known technologies and practices.