LED lighting would be another example of something that's come in within the last 10 years -- unpredicted, unheralded -- the result of an innovation by a Japanese professor 20-30 years ago. But now we can get white or tunable light out of LEDs; uses far less electricity than the preceding technologies .... is yet another step in the incredible decline of the cost of lighting. That's my favorite example of rational optimism. You basically have to work for a third of a second these days on the average wage to earn an hour of light. Well back in 1800 you had to work for six hours to earn that much light from a candle on the average wage. That's the sort of improvement we've seen in technologies over the last couple of centuries.
You can see the