In this article, the author carries out a historical reconstruction exercise of some of the elements that make up the European mindset in the 16th and 17th century, in terms of demology, belief in the father and religious struggles; to contextualise Freud’s letter on a ‘17th century demonial neurosis’. It shows that painter Haizmann had at his time, the conceptions of the dementia, virgin and heartworms of his personal fatherhood complex, explaining his neurosis, but also the hypothesis that the collapse of the father’s figure, based on the Christian polytheism, and the loss of the religious hegemony of the Catholic Church as a result of the reform, growing scepticism – not of atheism – puts the whole era at a time of change of mindset from a closed world of dioses and dimonies to a positive, scientific and anxious universe due to the death of the protective father.