The book "Sustainable Fossil Fuels" suggests that we can keep using fossil fuels like oil, gas, and coal without harming the environment or causing other problems. The author argues that with new technology, we can use these fuels in a cleaner way. This transition to using unconventional sources of fossil fuels can help us reduce greenhouse gas emissions, make energy more secure, and support economic growth in poorer countries. By improving energy efficiency, developing renewable energy, and enhancing nuclear power, we can create a sustainable energy system while still using fossil fuels for now.