The real "movement" of the sciences takes place in the revision of these basic concepts, a revision which is more or less radical and lucid with regard to itself. A science's level of development is determined by the extent to which it is capable of a crisis in its basic concepts. In these immanent crises of the sciences the relation of positive questioning to the matter in question becomes unstable. Today tendencies to place research on new foundations have cropped up on all sides in the various disciplines.
The discipline which is seemingly the strictest and most securely structured, mathematics, has experienced a "crisis in its foundations." The controversy between formalism and intuitionism centers on obtaining and securing primary access to what should be the object of this science. Relativity theory in physics grew out of the tendency to expose nature's own coherence as it is "in itself." As a theory of the conditions of access to nature itself it attempts to preserve the immutability of the laws of motion by defining all relativities; it is thus confronted by [10] the question of the structure of its pre-given area of knowledge, that is, by the problem of matter. In biology the tendency has awakened to get behind the definitions that mechanism and vitalism have given to organism and life and to define anew the kind of being of living beings as such. In the historical and humanistic disciplines the drive toward historical actuality itself has been strengthened by the transmission and portrayal of tradition: the history of literature is to become the history of critical problems. Theology is searching for a more original interpretation of human being's being toward God, prescribed by the meaning of faith itself and remaining within it. Theology is slowly beginning to understand again Luther's insight that its system of dogma rests on a "foundation" that does not stem from a questioning in which faith is primary and whose conceptual apparatus is not only insufficient for the range of problems in theology but rather covers them up and distorts them.
Fundamental concepts are determinations in which the area of knowledge underlying all the thematic objects of a science attains an understanding that precedes and guides all positive investigation. Accordingly these concepts first receive their genuine evidence and "grounding" only in a correspondingly preliminary research into the area of knowledge itself. But since each of these areas arises from the domain of beings themselves, this preliminary research that creates the fundamental concepts amounts to nothing else than interpreting these beings in terms of the basic constitution of their being. This kind of investigation must precede the positive science&-and it can do so. The work of Plato and Aristotle is proof of this. Laying the foundations of the sciences in this way is different in principle from "logic" limping along behind, investigating here and there the status of a science in terms of its "method." Such laying of foundations is productive logic