A useful analogy is to see traditional societies as relying on instantaneous (or minimally delayed) and constantly replenished solar income, while modern civilization is withdrawing accumulated solar capital at rates that will exhaust it in a tiny fraction of the time that was needed to create it.
Vaclav Smil...no matter how complex or affluent, human societies are nothing but subsystems of the biosphere, the Earth's thin veneer of life, which is ultimately run by bacteria, fungi and green plants.
Vaclav SmilI've read about 80 books a year for the past 50 years. I come from cultural breeding. I don't have a cellphone. When you spend all your time checking your cellphone messages, or updating your Facebook (of course I don't have a Facebook page) then you don't have any time for reading.
Vaclav SmilEnergy is the only universal currency: one of its many forms must be transformed to another in order for stars to shine, planets to rotate, plants to grow, and civilizations to evolve.
Vaclav Smil