One measure of how radically life has improved over the centuries is how much nighttime illumination can be purchased from a certain amount of labor.
For example, George Washington calculated that it cost him £5 a year to provide himself five hours of reading light every evening. That is the equivalent of about $1,000 today.
Imagine spending $83 a month to light only one lamp in your entire house.
We are amazingly rich today.
This insight provided by Human Progress on 2/15/17: How the cost of light has fallen by a factor of 500,000.
Here are some reference points provided by the article:
- Prehistoric times – chop wood 10 hours a day for six days, or 60 hours of work for 1,000 lumen hours, which is equal to a modern bulb burning for 54 minutes.
- George Washington – mid or late 1700s – 5 hours of candles a day cost equivalent of $1,000 a year.
- 1900 – it cost 60 hours labor for 10 days of light bulb. Oh, that would be 100 times brighter than Pres. Washington’s candles and without flickering or odor.
- 1920 – 60 hours would pay for 5 months light
- 1990 – 60 hours would pay for 10 years
- 2017 – same amount of labor will pay for 52 years of a light bulb. Oh, the math on that assumes running the light bulb 24 hours a day.
Use that as an indicator of how so much more rich we are today than 200 years ago, and especially compared to 1000 years ago. Here are the hard numbers :
- prehistoric, I’ll assume 2000 B.C. – .9 hours
- 1900 – 10 days, or 240 hours
- 1920 – 5 months, or 3600 hours
- 1990 – 10 years, or 87,600 hours
- 2017 – 52 years, or 455,520 hours
Here is the info even more compressed:
| year | hours light from 60 hours work |
| prehistoric | 0.9 |
| 1900 | 240 |
| 1920 | 3,600 |
| 1990 | 87,600 |
| 2017 | 455,520 |
I tried graphing the data, but the timeline is so extreme, I can’t get the graph to work.