Laboratory experiments are the principal tools used by psychologists to formulate and test their theories of how the human mind works, yet few histories of psychology have studied the experimental method and how it has changed over time. In this book then distinguished scholars explore the rapid rise and spread of the experimental method from its origins in the early decades of the century. They deal with such topics as the first efforts to bring number and quantification into psychology; who the subjects of early experiments were and how experimenters and subjects related to each other; famous psychologists such as Lewis Terman and Edward Titchener; and how experimental strategies were extended beyond the laboratory to the larger spaces of everyday life. The book concludes with two essays that discuss contemporary concerns regarding psychological experimentation.