In our survey of praxeology, historical examples will occasionally be used for two purposes:

To illustrate and concretize principles. Such illustrations remind us that praxeology deals with reality—with real institutions and processes affecting lives and happiness of human beings—and not with mere floating abstractions. Such historical references are not intended or required to demonstrate the validity of praxeological laws, since logical reasoning will already have been provided toward that end. This author (like any human being) has limited knowledge, and the student may sometimes disagree with his application of praxeological principles to a given historical situation. Such disputes, however, do not cast doubt on the principles themselves, since the historical situations are not advanced for purposes of proof. If one doubts a praxeological principle, then one should use a logical rather than a historical method, retracing the reasoning that underlies the principle, seeking to determine whether its premises are valid and whether the reasoning based on those premises is correct.
Historical references will also shed light on specific institutions (such as the US government) and ideas (such as "capitalism") that inevitably command our attention in practical political or social analysis.

Let us now return to Section 3, examining and comparing the leading ethical viewpoints.