Vampires
Especially important is his part in the fight against superstition during the enlightenment, particularly in the case of the vampires, that were reported from villages in Eastern Europe in the years between 1718 and 1732. After the last of the wars against the Turks in 1718 some parts of the land, e.g. Northern Serbia and a part of Bosnia, went to Austria. These parts were settled with refugees that had the special status of duty-free farmers. But for that they had to take care of the agricultural development and secure the frontier. Because of that the reports about the vampires reached for the first time German-speaking area. In the year 1755 Gerard van Swieten was sent by Empress Maria Theresa to Moravia to investigate the situation relating to vampires. He viewed the vampire myth as a "barbarism of ignorance" and his aim was to eradicate it.
His report, Abhandlung des Daseyns der Gespenster (or Discourse on the Existence of Ghosts), offered an entirely natural explanation for the belief in vampires. He explained the unusual states in the graves with possible causes such as the processes of fermentation and lack of oxygen which was a reason for preventing decomposition. Characteristic for his opinion is this quotation from the preface to his essay of 1768: “… that all the fuss doesn't come from anything else than a vain fear, a superstitious credulity, a dark and eventful imagination, simplicity and ignorance among the people.”
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