The Lindwurm, according to celtic myth, is a spirit to which is attributed the faculty to transfer its knowledge to who invocates it.
Contemporary esotericists believes the Lindwurm was the description of a phenomenon caused by the effect of an Eggregore which had begun to form thousands of years earlier, probably still in Mesopotamia, from the first ancestors who celebrated the rites, that contemplates the invocation of the Lindwurm or the invocation of entities that are considered to be its predecessors.
Some traditions, tells rules passed to posterity, related to those rites, imposed to never write or depict anything that represents what the Lindwurm really is, but just the Dragon that symbolizes it.