Chapter Two – Closer to Reality

In this small and deceptively simple chapter Deutsch tells the story of looking at stars and galaxies on a photographic plate. When he wonders about one particularly hard-to-classify smudge on one plate, he is told that it is neither a star nor a galaxy, but just an imperfection in the photographic emulsion.

But of course, all the images on the plate are made of the same stuff. Why is one a galaxy and the other just a mistake? Deutsch here reinforces the idea that all observations are theory-laden. There is nothing particularly remarkable about a smudge on a photographic plate. Only by applying the correct theory does the wonder come out. This is an image of a galaxy, hundreds of billions of stars all found millions of light-years away. Without theory to explain it to us, they’re all just smudges.

Good explanations open the world to our sense of wonder. A rock can be just a rock, or it can be the result of hundreds of millions of years of geologic processes, an artifact from our planet’s past. Maybe it contains a fossil, but fossils themselves only become meaningful when placed into context by a good explanation.

At COSI we have a cloud chamber. In looking inside the cloud chamber, one can see either little puffs of smoke, or through a good explanation one can see pieces of atoms flying apart, powered by the energy of radioactive decay, first stored in a supernova explosion billions of years in the past. That’s the sense of wonder that a good explanation can bring.