In 1433, artist Jan van Eyck invented an entirely new genre of painting while sitting quietly in his studio in Bruges. He did it with the help of a scientific breakthrough which allowed German engineers to create some of the world's first high-quality mirrors. The new German mirrors were made by coating glass with an amalgam of tin and mercury. Reflections in these mirrors were sharper than anything the world had ever seen, and they led to van Eyck's crazy idea to create a self-portrait.
It is absolutely crazy to think that what we call a mirror today has only existed for 600 years. For thousands of years, people had always seen reflections of themselves that were either colored by the metal that reflected them or distorted by the way the glass was made. The reflections were apparently so poor, no one even thought to paint themselves from one.
From the wikipedia article on mirrors:
The problems of making metal-coated, glass mirrors was due to the difficulties in making glass that was very clear, as most ancient glass was tinted green with iron. This was overcome when people began mixing soda, limestone, potash, manganese, and fern ashes with the glass. There was also no way for the ancients to make flat panes of glass with uniform thicknesses. The earliest methods for producing glass panes began in France, when people began blowing glass bubbles, and then spinning them rapidly to flatten them out into plates from which pieces could be cut. However, these pieces were still not uniform in thickness, so produced distorted images as well. A better method was to blow a cylinder of glass, cut off the ends, slice it down the center, and unroll it onto a flat hearth. This method produced the first mirror-quality glass panes, but it was very difficult and resulted in a lot of breakage. Even windows were primarily made of oiled paper or stained glass, until the mid-nineteenth century, due to the high cost of making clear, flat panes of glass.
We talk about how much our lives have changed in a short time because of the prevalence of cameras, and we wonder how having such devices will impact our psychological development. Sometimes its important to remember that humanity has had many similar advances which drastically alter how we physically view ourselves. I don’t think many people consider mirrors and windows modern conveniences, but we probably should.