The study of political theory has shifted through different approaches, with behaviouralism and institutionalism being two major paradigms. Both seek to understand politics scientifically but differ in focus and methods.

The institutional approach is traditional, studying politics through formal structures such as legislatures, executives, courts, and constitutions. It emphasizes legal frameworks, procedures, and authority. Institutions are seen as determinants of political behaviour, shaping stability and governance. Institutionalism is normative, descriptive, and largely formal, often ignoring informal dynamics of politics.

In contrast, the behavioural approach emerged in the mid-20th century, focusing on individuals, groups, and their political behaviour. It uses empirical methods, surveys, and statistical analysis to study attitudes, voting patterns, and decision-making. Behaviouralism emphasizes observable behaviour rather than normative ideals. Its principles—regularities, quantification, verification, and value-neutrality—mark it as a scientific approach.

The comparison reveals key differences:

Focus – Institutionalism studies structures; behaviouralism studies behaviour.

Method – Institutionalism is descriptive and legalistic; behaviouralism is empirical and quantitative.

Normativity – Institutionalism is value-laden; behaviouralism is value-free.

Scope – Institutionalism emphasizes formal authority; behaviouralism includes informal and psychological factors.

Despite differences, they complement each other. Modern political science often integrates both, recognizing that institutions shape behaviour and behaviour influences institutions. Neo-institutionalism reflects this synthesis by re-emphasizing institutions while using behavioural insights.

Thus, while behaviouralism expanded the discipline’s scientific base, institutionalism provided its structural foundation. Their comparative study shows the evolution of political analysis from formalism to empiricism.