The purpose of this note is to clarify how the idea of "causal depth" can play a role in finding the more "approximately true" explanation through causal comparisons. It is not an exhaustive treatment but rather focuses on a few aspects that may be the most critical in evaluating the explanatory strengths of a theory in the social sciences. It presents a general argument which is anti-Humean on the critical side and scientific realist on the positive side. It also elucidates how explanations in political economy and other social sciences can be judged by the scientific realist criterion of causal depth by an extensive example from research in the political economy of development. In this case, an "intentional" and methodologically individua...