At the dawn of man, early humans fought battles for fire. In the Dark Ages, a candle was a piece of technology. Now, we just switch the light on. The invention of Edison's lightbulb marked the end of an era in which we had to make light with fire. Making and maintaining light with fire takes an effort so it becomes valuable.
After Edison, artificial lighting became easy: a lightbulb always burns (till it blows). By lighting virtually everything, day and night, we abandoned darkness. Light became self-evident and meaningless. There is always such an abundance of light, we don’t “see” it anymore.
By looking through the welding mask, we can see the light very clearly in every little detail. Looking directly into the light would blind us. Therefore the mask provides us with the necessary darkness. Through darkness, we see the light.
"Ik zie het licht. In elke lamp." Luc De Vos