There is an idea that appears across science, math, and philosophy: simple explanations often seem to work better than complicated ones. This idea is usually called Occam’s Razor , which says that when two explanations fit the same facts, we should prefer the simpler one. Scientists use it when choosing between theories. Mathematicians use it when deciding which proof feels the most satisfying. Even everyday reasoning relies on it when we choose the explanation that requires fewer assumptions. But why does this principle work so well? Does the universe really favor simplicity, or is simplicity only a habit of human thinking? Why Do Simple Theories Work? Occam’s Razor was first written about by medieval philosopher William of Ockham. He believed that explanations should not multiply entities without necessity. In modern terms, a theory should only include what it needs to make correct predictions. If two theories both match the data, the simpler one usually generalizes better...