There are periods in the growth of science when it is well to turn our attention from the imposing superstructure and to examine the foundations. The foundation of science is the scientific method; the unity of the sciences reflects the method and not the material. Karl Pearson observed that the method of science is characterized by careful accurate observation, by classification of the data in sequence and correlation, by the recognition of scientific laws, by self-criticism, and by the final criterion of acceptance and confirmation by others.
The scope of science is to ascertain truth in every branch of knowledge. How does psychiatry measure to the rule of the scientific method? Descriptive psychiatry derives from correlated data; the clinical pattern can usually be fitted to a "disease" listed in the diagnostic manual of the American Psychiatric Association. Psychiatric research in biochemistry and physiology also reflects the methods of the natural