Most psychotherapeutic approaches are based on some personality theory. In previous posts, I have been saying that, despite claims to the contrary, these theories are not, and cannot be supported by scientific research. What is my basis for making this assertion?
Psychology may be ineffective, especially in the development of major theoretical structures, because work with humans presents the researcher with an overwhelming number of variables. For example, in the study of anger, the researcher would need to consider genetic factors, physiological factors such as potential brain injuries, health, and diet, the past nurturing of the subject, the person’s present situation including various relationships and stresses, his lifestyle and thought patterns, the individual’s spiritual life, and many other factors. Within each of these categories, there exists virtually thousands, if not millions, of other potential variables. In a scientific study, the task of the researcher is to isolate variables so that he can study the influence of one variable on another. In the study of human personality, the overwhelming number of variables makes this task extremely difficult, if not impossible. The researcher may use control groups and other methods in an attempt to overcome these complexities. Yet, the task is daunting.
And the challenge becomes heightened as the researcher seeks to broaden the scope of inquiry. A study determining the correlation between blood pressure and anger would seem a relatively easy experiment. However, even a simple experiment such as this would include serious challenges. The researcher would need to establish some criterion or criteria for determining levels of anger such as providing the subject with a scale of 1 to 5, and defining the symptoms at each level. It is apparent that such an approach is rather subjective. There is also the challenge of determining what impact being involved in an experiment would have on the subject’s blood pressure. The real challenge in this type of experiment is filtering out factors that are affecting blood pressure other than anger. For example, it would be interesting to determine if gender issues might effect the results. If the subjects were male, it would be interesting to determine if having a female take the blood pressure would produce different results that having a male perform this task. The age, appearance, and personality of the person taking the blood pressure might even be a factor. Time of day, temperature of the room, the atmosphere within the room, lighting, time since the subject’s last meal and what he ate, number of other people in the room, comfort of the chair on which the person is seated, and many other factors could influence the results.
A good researcher will seek to standardize as many factors as he can. However, as we can see, it is virtually impossible to account for every factor. No doubt the person’s health, what he is thinking about at the moment, previous bad experiences with experiments, and a multitude of other variables also come into play.
Even if the researcher was able to filter out all of these extraneous variables, because this is a relatively simple experiment it does not tell us a great deal about human beings. If the researcher seeks to delve into more profound issues, such as the relationship of marital happiness to anger, the difficulties increase exponentially. Among the challenges is the question of cause and effect. In studying the connect between anger and marital happiness, it would be difficult to determine whether the anger disrupted marital happiness or the lack of marital happiness created the anger, or whether each was influencing the other to some degree. The latter would probably be the case, which would make understanding the relationship between the two all the more complex, and lead to the question of what level of influence each of these factors exerted over the other.
The point is that in dealing with human beings there seems to be no end to the complexities, and the more comprehensive the objective of a study, the more complex it becomes. Therefore, being scientific about even simple issues is difficult, and dealing scientifically with overarching psychological topics is virtually impossible. This is at least one reason why social sciences have not produced the results enjoyed by natural sciences. It also explains why the personality theories developed by psychologists cannot be good science. We can discover some things about people through research, but a broad personality theory is beyond the scope of scientific research.
In our next post, we plan to deal with another factor placing the development of personality theories beyond the realm of scientific research.