The work ethic we have adopted today says that we should do away with sleep, or at least eliminate as much sleep time as possible. The movers and shakers of the world don't waste their time sleeping. Yet too little sleep can kill us outright or can cause a gradual deterioration in our health. Too little sleep can make us clumsy, stupid, and accident-prone. Too little sleep can destroy our psychological motivation and put us into a deep depression.
People regularly sleep less now than before the lightbulb was invented.
A similar study was conducted back in 1910. The timing is important because it was in 1913 that our modern tungsten filament lightbulb was introduced. Earlier versions of the lightbulb had a carbon filament in a globe from which the air had been pumped out to provide a reasonable vacuum. This was the lightbulb that provided the cheap, bright, and long-lasting electric light we have come to take for granted. It was this lightbulb that made it possible for working people to free themselves from the darkness of night.