Kerby Anderson

There are many modern conveniences we take for granted. Near the top of that list is light. To be more precise, we take for granted artificial light, except when our lights go out. But light as a product illustrates the benefits of modern technology. A story in Human Progress explains how “light has turned from something too precious to use into something everyone can afford.” It used to take 10 hours a day for six days to produce 1,000 lumen hours of light. To put that in perspective, that is equivalent to “one modern light bulb for just 54 minutes.” When candles came along, this provided light for wealthier people but was prohibitively expensive for the common person. By the 18^th century, candles made from the waxy substances in the head cavities of sperm whales were less time-consuming. But they were still expensive, not to mention terminal for the whales. George Washington even calculated the annual cost to him for the opportunity to have five hours of reading per night. The light bulb changed everything. By 1900, 60 hours of work could provide 10 days of light. Twenty years later, 60 hours of work could pay for five months of light. Today, that same amount of work can produce 52 years of light. “The amount of labor that once bought 54 minutes of light now buys 52 years of light. The cost has fallen by a factor of 500,000 and the quality of that light has transformed from unstable and risky to clean, safe, and controllable.” Sadly, many in other parts of the world don’t have access to that light, which is even more reason for us not to take it for granted.