especially when the presupposed understanding still operates in the common knowledge of human being and world? But according to the most elementary rules of logic, the circle is a circulus vitiosus. If this is so then the business of historical interpretation is thus banned a priori from the realm of rigorous knowledge. If the fact of the circle in understanding is not eliminated, historiography must be content with less rigorous possibilities of knowledge. It is permitted to compensate for this defect to some extent with the "spiritual significance" of its "objects." But even according to the opinion of historiographers themselves, it would be more ideal if the circle could be avoided and if there were the hope of finally creating a historiography which is as independent of the standpoint of the observer as the knowledge of nature is supposed to be.
[153] But to see a vitiosum in this circle and to look for ways to avoid it, even to "feel" that it is an inevitable imperfection, is to misunderstand understanding from the ground up. It is not a matter of assimilating understanding and interpretation to a particular ideal of knowledge which is itself only a degeneration of understanding that has strayed into the legitimate task of grasping of what is objectively present in its essential unintelligibility. Rather, the fulfillment of the fundamental conditions of possible interpretation lies in not failing to recognize beforehand the essential conditions of the task. What is decisive is not to get out of the circle, but to get into it in the right way. This circle of understanding is not a circle in which any random kind of knowledge operates, but it is rather the expression of the existential fore-structure of Dasein itself. The circle must not be degraded to a vitiosum, not even to a tolerated one. A positive possibility of the most primordial knowledge is hidden in it which, however, is only grasped in a genuine way when interpretation has understood that its first, constant, and last task is not to let fore-having, fore-sight, and fore-conception be given to it by chance ideas and popular conceptions, but to secure the scientific theme by developing these in terms of the things themselves. Because, in accordance with its existential meaning, understanding is the potentiality for being of Dasein itself, the ontological presuppositions of historical [historischer] knowledge transcend in principle the idea of the rigor of the most exact sciences. Mathematics is not more exact than history, but only narrower with regard to the scope of the existential foundations relevant to it.
The "circle" in understanding belongs to the structure of meaning, and this phenomenon is rooted in the existential constitution of Dasein, that is, in interpretive understanding. Beings which, as being-in-the-world, are concerned about their being itself' have an ontological
* This "its being itself" is, however, intrinsically determined by the understanding of being, that is, by standing within the clearing of presence, where neither the clearing as such nor presence as such becomes thematic for representational thinking.