[H]istorical science is not worse, more restricted, or less capable of achieving firm conclusions because experiment, prediction, and subsumption under invariant laws of nature do not represent its usual working methods. The sciences of history use a different mode of explanation, rooted in the comparative and observational richness in our data. We cannot see a past event directly, but science is usually based on inference, not unvarnished observation (you don't see electrons, gravity, or black holes either).
In some central and important cases, ... the existence of specific power relations in the society will produce an appearance of a particular kind. Certain features of the society that are merely local and contingent, and maintained in existence only by the continual exercise of power, will come to seem as if they were universal, necessary, invariant, or natural features of all forms of human social life, or as if they arose spontaneously and uncoercedly by free human action.raymond geuss
[Critical social science attempts] to determine when theoretical statements grasp invariant regularities of social action as such and when they express ideologically frozen relations of dependence that can in principle be transformed.jürgen habermas