Paranoiac delusion has the particularity of being contagious... In this context, the psychological mechanisms at work are notably the collusion between the melancholic core of the paranoiac and the traces of unresolved pathological mourning in the "paranoee". One of the most essential mysteries to be solved in the field of the human psyche lies in the delusional contagion of paranoia. In fact, the only delusion capable of operating by contagion is paranoiac delusion...