Ideally, scientific laws should display the virtues of precision and generality, as do the laws of physics  However, because of the nature of their subject matter, laws of social science often have to use terms that are imprecise: for example, one knows only vaguely what is meant by republicanism or class
As for generality, laws that apply only in certain social systems are typically the only ones possible for the social sciences
All else being equal, a precise, general scientific law is to be preferred over one that is not general.