Another tendency that is highly characteristic of all cultures is the rationalistic explanation of what reason never gave rise to. This is shown very clearly in the justification of existing cultural features or of opinions acquired as a member of a particular society. Hegel’s notion that whatever exists is rational and Pope’s ‘whatever is, is right’ have their parallels in primitive legend and the literature of religious and political partisanship. In the special form of justification employed we find again the determining influence of the surrounding cultural atmosphere. Among the Plains Indians almost everything is explained as the result of supernatural revelation; if a warrior has escaped injury in battle it is because he wore a feather bestowed on him in a vision; if he acquires a large herd of horses it is in fulfilment of a spiritistic communication during the fast of adolescence. In a community where explanations of this type hold sway, we are not surprised to find that the origin of rites, too, is almost uniformly traced to a vision and that even the most trivial alteration in ceremonial garb is not claimed as an original invention but ascribed to supernatural promptings. Thus, the existing culture acts doubly as the determinant of the explanation offered for a particular cultural phenomenon. It evokes the search for its own _raison d’être_; and the type of interpretation called forth conforms to the explanatory pattern characteristic of the culture involved. Culture thus appears as a closed system. We may not be able to explain all cultural phenomena or at least not beyond a certain point; but inasmuch as we _can_ explain them at all, explanation must remain on the cultural plane.