in its planning and execution, is supported and guided by what is postulated as a fundamental law, in order to bring forth the facts which either confirm the law or deny it such confirmation. The more exact the projection of the ground-plan of nature the more exact is the possibility of experiment. The often mentioned medieval scholastic, Roger Bacon, can, therefore, never be the forerunner of the contemporary experimental researcher but remains, rather, merely the successor of Aristotle. For in the meantime, genuine possession of the truth has, through Christianity, been transferred to faith — to the truth preserved in the written word and in church doctrine. The highest knowledge and teaching is theology considered as interpretation of the divine word of revelation that is recorded in scripture and proclaimed by the Church. Here, knowledge is not research but rather right understanding of the normative word and of the authorities who proclaim it. For this reason, discussion of the words and doctrinal opinions of the various authorities takes precedence in the process of knowledge-acquisition in the Middle Ages. The componere scripta et sermones, the argumentum ex verbo, is decisive and, at the same time, the reason why the Platonic and Aristotelian philosophy that had been adopted, had to become scholastic dialectic. If, then, Roger Bacon demands the experimentum — as he did — what he means is not the experiment of science as research. Rather he demands, in place of the argumentum ex verbo, the argumentum ex re;2 instead of the discussion of doctrinal opinions, observations of the things themselves, in other words, Aristotelian ἐμπειρία.

The modern research-experiment is, however, not merely an observation that is more precise in degree and scope. It is, rather, an essentially different kind of methodology for the verification of law within the framework and in the service of an exact projection of nature. In the historical human sciences "source criticism" corresponds to the experiment of physical research. This name covers, here, the whole range of discovery, examination, verification, evaluation, preservation, and interpretation. It is indeed true that the historical explanation based on source-criticism docs not subsume the facts under laws and rules. Yet it is not reduced to a mere reporting of the facts. As in the natural sciences, method in the historical sciences is aimed at presenting the constant and at making history an object. History can only be objectified when it is something past. The constancy of the past, that on the basis of which historical explanation takes into account the unique and diverse in history, is the having-always-already-been-there, that which can be compared. Through the constant comparisons of everything with everything else the intelligible is worked out and, as the ground-plan


The Age of the World Picture (GA 5) by Martin Heidegger