The Concepts of Psychiatry: A Pluralistic Approach to the Mind and Mental Illness

6 What Is Scientific Method in Psychiatry?

C H A P T E R 6 What Is Scientific Method in Psychiatry? To observation, with reasoned thought, the Greeks added experiment . . . the instrument which has made science productive. —WILLIAM OSLER, 1889 I believe that Karl Jaspers has provided the most tightly reasoned analysis of scientific method for psychiatry. One might summarize his contribution in this regard in two main ideas: methodological pluralism and the understandingexplanation dichotomy. 1. It is perhaps not an exaggeration to state that Jaspers was the first psychiatrist to clearly identify the need to be clear about one’s methods. Jaspers took it as a given that each human being, including each patient, is unique. There is an aspect of each person that transcends any attempt to understand or capture that person by a certain way of knowing, whether it be science or anything else. This transcendence is the ultimate source of human freedom, Jaspers believed . Simply recognizing that we are each unique could also be understood biologically, I believe, as resulting from genetic differences, however small, between individuals. No matter how one views human freedom, Jaspers begins with this first intuition: that a human being can never be completely understood by a single method of knowledge. If one begins with this assumption, one is led inexorably to its corollary: every method of knowledge has its limitations . If no single method is sufficient, then multiple methods should be used. Complementary information should be obtained with multiple methods, leading to a better and better understanding of an individual’s mental life or condition. Yet multiple methods never exhaust the uniqueness of individu- als; hence clarity about one’s methods is essential. Each method has an advantage and strength, capturing certain aspects more effectively and accurately than other methods; and each method has disadvantages and weaknesses, overlooking certain aspects. Each method begins with certain assumptions, thereby both honing its ability to capture certain aspects of reality and limiting its ability to capture other aspects of reality. Methodological consciousness, then, consists of recognizing the strengths and limits of each method and applying the ones that are best suited for specific circumstances (diseases, diagnoses , conditions). This was perhaps Jaspers’s most important contribution to a theory of scientific method for psychiatry. 2. This pluralism is closely tied to another idea that Jaspers introduced into psychiatry: the understanding-explanation distinction. This did not originate with Jaspers, but he was the first person to apply it systematically to psychiatry. By understanding (Verstehen), Jaspers referred to “meaning,” or the psychological intuition that an individual could have about the meaning of a psychological state or event for another individual. By explanation (Erklaren), Jaspers referred to the more traditional concept of causal empirical experience, or the observable influence of one event or process on another that could be tested objectively . Thus, on the one hand, if one observes that throwing a rock breaks a window, and one conducts tests in which different individuals throw rocks at different windows, and each time the windows break, one is engaging in causal explanation and concludes that the throwing of rocks at windows causes the windows to break. On the other hand, if one observes that a certain person is throwing a rock at a particular window, and one wants to know why that person is throwing the rock, one might conjecture that that person is throwing the rock to get the attention of the person who lives inside that house. This line of thinking is an exercise in understanding, or trying to find meaning for an event. Wilhelm Dilthey argued that this explanation-understanding distinction applied to the natural versus the human sciences (Makkreel 1992). That is, in natural sciences (physics, chemistry, biology), causal explanation worked well and was sufficient to understand those fields of knowledge. However, in human sciences (Dilthey focused on history), understanding was required. For instance, why did Napoleon invade Russia? A causal explanation approach would focus perhaps on economic factors that served as background What Is Scientific Method in Psychiatry? 79 for the events of the time, or even perhaps on Napoleon’s physiological state (his bodily and brain function); yet this would seem insufficient. A historian following the understanding approach would try to place herself in Napoleon’s place; faced with certain economic and political facts, and armed with her education , background, and beliefs, the historian could surmise that Napoleon might have had certain...