In his book 'Cock Lane and Common-Sense', Andrew Lang explores the uneasy relationship between anthropology, folklore, and psychical research when it comes to abnormal experiences like ghosts, fire-walking, and crystal-gazing. While anthropology and folklore are willing to accept these phenomena as part of tradition and belief, they often reject modern first-hand accounts. Meanwhile, psychical research focuses on contemporary experiences but neglects the historical and traditional evidence. Lang argues that both fields should work together and consider all forms of evidence to fully understand these phenomena. As such, he attempts to do so in this book, which he concludes by calling for more scientific experimentation in exploring the origins of these beliefs.