Do the symbols carved in the stone above represent a complex written language—or are they merely religious imagery? That's the mystery scientists have been trying to solve ever since they laid their eyes on Pictish Symbol Stones made by an Iron Age Celtic people known as the Picts between 300 C.E. and 843 C.E. Now researchers have analyzed the images of stags, wolves, and mythical beasts, as well as abstract rectangles, disks, and lines, with a statistical algorithm that differentiates between random character strings and those conveying meaning. Based on the order in which they appear, the images on the Pictish stones were likely a writing system in which each symbol represented a word, like the Chinese alphabet, concludes a paper in this week's Proceedings of the Royal Society A: Mathematical, Physical, and Engineering Sciences. Since most knowledge of Pictish society comes from outside sources—such as the Romans, Anglo-Saxons, and Irish—this writing, if deciphered, could give historians the Pictish view of their own history.