All of humanity's feats, whether a record-setting deadlift by the world's strongest man or the construction of a gleaming city by a technologically advanced economy, originate from a single hidden source: positive net energy. Having surplus energy in the form of thirteen pounds of food per day enables a very big man, Hafthor Bjornsson, to lift very big objects. Similarly, having surplus energy in the form of fossil fuel enables very big societies to build and trade very big piles of stuff. Maybe Hafthor has a rock-solid plan for keeping his dinner plate well stocked, but no society seems ready to have a mature conversation about how our sprawling cities and nations will manage as net energy declines. Calling our conversation "mature" might be a stretch, but at least we're willing to address climate change, sustainability, and the rest of the net energy conundrum head on. Alice Friedemann, author of Life after Fossil Fuels, joins the conversation.