The history of light (classic)

Artificial light serves as a powerful metric for tracking human economic progress and productivity. Historically, light was a scarce, labor-intensive commodity; in ancient Babylon, a full day’s wages yielded only ten minutes of light. Over centuries, incremental improvements—from animal fat candles to kerosene—gradually lowered costs. The 19th-century shift to electric light, facilitated by Thomas Edison’s integration of scientific innovation with robust financial systems and corporate structures, accelerated this trend. By the 1990s, a day’s labor could purchase 20,000 hours of light, illustrating the exponential growth in efficiency that defines modern economies. This trajectory demonstrates that economic growth is fundamentally driven by discovering ways to accomplish tasks with significantly less effort, ultimately allowing society to move beyond subsistence and access resources once reserved for the wealthy.