The adoption of the quantitative methods in Political Science has taught one tiling to the students of Political Science, viz., the language of variables. It is something which they did not know or practice before the “behavioural revolution” of 1950′s, because Political Science was then a traditional, legal and institutional study. By a variable we mean any trait, quality, characteristic, or condition which can vary in magnitude in different individual cases, e.g. the opinion of the party voters or the changes in public opinion.
One of the essential features of a variable is that it can be measured or quantified. For example, it can be computed that a certain number of voters favour one political party, while another number of them favour another party and so on. Moreover, on the basis of variables, if is possible to form a hypothesis which can be substantiated or proved by further data collection by survey and analysis and the future trends can be predicted. In short, these developments in Political Science have made it a more exact social science than ever before.
To conclude, the sciences of statistics, psychology and sociology and the application of quantitative methods to political data will enhance still more the claims of Political Science to be considered as an empirical science. A number of political acts behaviour and processes are statistical in nature, e.g. voting. Now, if a large number of facts are collected and studied with the aid of these methods and techniques, if the area from which these facts are gathered is wide and great care is taken in analysing them in relation to their environment, there would be greater-possibility that the conclusions and generalisations would be more precise, exact and valid than otherwise. “We can become, “writes Dr. Finer, “the prophets of the probable, if not the seers of the certain.”
Science is measurement. The more the methods and techniques of measuring and quantifying the political events, processes and phenomena are developed, the more Political Science will become scientific and predictive. As Maurice Duverger puts it: “Politics is much more scientific in 1964 than was in 1870. Statesmen can and do effectively use statistics, manipulation of the masses and so on. However, we now know that the area covered by this scientific kind of politics is much smaller than that of politics as an art, based upon imprecise materia] that is not measurable but is intuitive and irrational”.
The purpose of Political Science is to show why and how the politicians, Statesmen and citizens act in given situations but not to make choices for them in actual situations, which is the function of the art of politics. “It can make clear the real terms of choice, but it cannot choose”.