Why do we believe in electrons, but not in fairies?
by Benjamin Kuipers No one has directly observed either electrons or fairies. Both of them are theoretical constructs, useful to explain observations that might be difficult to explain otherwise. The "theory of fairies" can actually explain more things than the "theory of electrons". So why do we believe in electrons, but not in fairies? Is the issue a political one, where the "electron" fans got the upper hand in the nineteenth century, so by the twentieth century the "fairy" fans were a scorned and persecuted minority? No, to both. Fairies are much more free. It's always possible that there really are fairies. The scientific method is an amazing procedure for incrementally improving certain kinds of theories: those that make testable predictions. The theory of evolution is a scientific theory, because it implies a large number of specific testable claims. The theory of intelligent design could be true. The scientific method is an enormous intellectual asset to the human race.