Geology

In collecting the primary geologic data, some personal capacities of the geologist (such as strong physique, perceptive faculties, perseverance, talent for drawing) are generally of much greater importance than in any of the sister sciences, which can rely on the quality of the instruments used in collecting primary data… Hans Cloos (1949) called this way of interrogation [by geologists] "the dialogue with the earth," "das Gespraich mit der Erde."

The past history of our globe must be explained by what can be seen to be happening now. No powers are to be employed that are not natural to the globe, no action to be admitted except those of which we know the principle.

The increasing number of factors playing a role in the various complexes of natural phenomena are the origin of new, so-called emergent, laws and characteristics. Based on this principle of emergence, a hierarchy of sciences can be distinguished: physics-chemistry-geology-biology-psychology.