In the beginning of the twentieth century, the science of human nature, called psychology, has provided a new approach to the study of Political Science. It was further influenced by Sigmund Freud’s theories and techniques of psychoanalysis. However, an English political scientist, named Graham Wallas, first emphasised the importance of psychology for Political Science as early as 1908.
He wrote: “the efficacy of Political Science, its power of forecasting die results of political causes, is likely to increase… because modern psychology offers us a conception of human nature much truer though more complex than that which is associated with the traditional English political philosophy., (and) under the influence and example of the natural sciences, political thinkers are already beginning to use quantitative rather than merely qualitative words and methods, and are able therefore both to State their problems more fully and to answer them with a greater approximation to accuracy”.
In short, psychological approach emphasises the use of quantitative methods in the study of Political Science. But this was only the beginning. The quantitative methods and techniques of Political Science were, however, fully developed by the behavioural political scientists nearly half a century after Graham Wallas, as we shall describe lata* on.