Once there was a dark lake, perhaps it was underground. Scholars settled by the lake intrigued, determined to understand it. Over the years they established an institute devoted to understanding the lake, with various approaches and theories as to the nature of that dark body of water. Eventually, they devised a technological approach. They invented drops of light that could be adjusted to sink a predetermined distance. Over time they dropped enough to illumine the whole lake. They could look into the lake now and understand it. The conclusion they drew was that it was a body of water filled with light.