This essay is dedicated to the fascinating cave systems, which appear again and again as a motif in myths, dreams or fairy tales due to their surreal landscapes. The tendency to mystification is based on the subterranean systems, which are sparsley accessible and which demand all kinds of imagination from the humans on the earth’s surface.

[…] The caves’s distinctive acoustic is leveled to echo. Echo also became a stylistic device par excellence in the Greek mythology and in further fairy tales with cave occurrences from regions all over the world. An echo (also called reverberation) occurs when reflections of a sound wave are delayed to such an extent that they can be perceived as a separate auditory event.

Concentrated and strong late reflections can be heard as separate echoes. A single separately perceived echo has the same pitch as the original, but the pitch is always lower than that of the original. The echo is an extraordinary monument, because it is usually acoustically perceptible, only partially visually recognizable but in no way haptically tangible. The echo can only be experienced temporarily and disappears again. In addition, it is too mostly a cave dweller and its existence is dependent on its environment.[…]

[…] The cave has also always been understood as an echo chamber, so to speak. The term has been used for quite some time to designate an epistemic construct of the present. This construct understands itself as an environment in which a person or group encounters only beliefs or opinions that coincide with their own, so that their existingviews are reinforced and alternative ideas are not considered. It does not suer from a lack in

connectivity; rather it depends on a manipulation of trust by methodically discrediting all outside sources. Members of echo chambers become dependent on the sources within the chamber and highly resistant to any external sources. […]

[…] This construct contradicts the understanding of caves, i.e. the prototypes of the so- called echo chamber. Caves are considered to be the emblematic place of fundamental knowledge transmission since prehistoric times. The contemporary construct echo chamber turns against the impulse of progress of a constant and expanding generation of knowledge and, above all as mentioned, it methodically and consciously closes itself to the exchange of knowledge. […]