Measuring Progress by the Cost of Light

Time is not the only life-enriching resource granted to us by technology. Another is light. Light is so empowering that it serves as the metaphor of choice for a superior intellectual and spiritual state: enlightenment. In the natural world we are plunged into darkness for half of our existence, but human-made light allows us to take back the night for reading, moving about, seeing people’s faces, and otherwise engaging with our surroundings. The economist William Nordhaus has cited the plung...