Beyond Nymphs, Dryads, and Leprechauns

How does science work? . . . The scientific method—famously objective, logical and eminently reliable; and the fruits of its success, both pure and applied, are the single most obvious factor in distinguishing the varying levels of progress between different human societies throughout history. But what happens when the experimental arena becomes less and less accessible?

"There is some sense that theoretical physicists, unencumbered by data from experiment, are just out there inventing leprechauns and fairies and nymphs and dryads around every corner, and every crazy idea you have is something that you can put out there. Of course we all agree that experiment decides, but until it does, anything goes: leprechauns and nymphs and dryads are all on the same footing. But it is just not like that."

Read more from Nima Arkani-Hamed, Professor in the School of Natural Sciences, on the reality of theoretical physics.