• The Perfect introduces a time interval: the “perfect time span” (PTS). • The Right Boundary (RB) of the PTS is set by Tense. • The Left Boundary (LB) of the PTS may be set by “perfect adverbials”. • The lower predicate (event) is predicated of the PTS, either directly or mediated by various devices, most notably operators associated with the Perfective or Imperfective. • When the predicate ha...

In the process of transition from old institutionalism to new institutionalism, theoretical foundation of old institutionalism was gradually enlarged and more research approaches were integrated. Firstly, rational aspects of behavioristic politics as borrowed. Then, its epistemology, its research target and research level are expanded. Finally, relevant theories of economics, sociology and hist...