The task of the philosophy of science, according to Churchman, is twofold. It is, one, “to determine the ideal of science by scientific methods,” and, the other, “to describe the manner in which science can most efficiently approach its ideals” (190). The primary purpose of this book on experimental inference is to deal with these two subjects as they bear upon what is commonly called material or empirical science, rather than upon formal or analytic science, though it is recognized that no absolute separation can be made between these two different types of science, or between the performance of the above tasks in connection with each. The kind of science, then, whose objective and methods are to be elucidated is the kind in which in some broad sense of these terms decisions are necessarily made on the basis of empirical observation and testing. Some observation or series of observations is made, and it is the task of the scientist to make an inference based upon these observational data. What is his aim in doing this, and what are the most efficient ways in which he can proceed?