In corporate and government bureaucracies, the standard method for making a presentation is to talk about a list of points organized onto slides projected up on the wall. For many years, overhead projectors lit up transparencies, and slide projectors showed high-resolution 35mm slides. Now "slideware" computer programs for presentations are nearly everywhere. Early in the 21st century, several hundred million copies of Microsoft PowerPoint were turning out trillions of slides each year.
Alas, slideware often reduces the analytical quality of presentations. In particular, the popular PowerPoint templates (ready-made designs) usually weaken verbal and spatial reasoning, and almost always corrupt statistical analysis. What is the problem with PowerPoint? And how can we improve our presentations?
We can easily imagine from our own experience why fire might be used as a symbol of the life of a house and the family that lives there. The fire was certainly the most lifelike element of the house: it consumed food and left behind waste; it could grow and move seemingly by its own will; and it could exhaust itself and die. And most important it was warm, one of the most fundamental qualities that we associate with our own lives. When the fire dies, its remains become cold, just as the body becomes cold when a person dies. Drawing a parallel to the concept of the soul that animates the physical body of the person, the fire, then, is the animating spirit for the body of the house.