Although bier-right, in comparison with other ordeals, plays so inconspicuous a part in the history of jurisprudence, it is especially interesting in one respect. As a judicial expedient, it did not spring into notice until after the other vulgar ordeals had been discredited and banished from the courts. It escaped the censure of the Church and was a survival of the Judgment of God, reaching its fullest development in the seventeenth century. It thus became the subject of investigation and debate in an age of critical tendencies and comparative intelligence. Among those who had faith in it there was much fruitless speculation to account for the result, and there was by no means a consensus of opinion as to the causes at work. In 1487 the inquisitor Sprenger takes a materialistic view and uses it as the basis of an argument on the wonderful properties of inanimate matter. He explains that air is introduced into the wound when it is inflicted, and that it rushes out when agitated by the presence of the slayer, bringing blood with it, but he adds that others believe it to be the cry of blood from the earth against the murderer, as related of the first homicide, Cain.[1166] About a century later Del Rio tells us that some looked upon it as a miracle, others as an accident, while he himself can see no better reason than the violent antipathy conceived by the slain for the slayer.[1167] Carena holds it to be the mysterious Judgment of God, unless it happens to be the work of the demon, and in this uncertainty concludes that if there are no other proofs it only justifies further investigation and not torture.[1168] Oelsner informs us that learned men disputed whether it was occasioned by antipathy or sympathy, by the remains of the soul in the body, by wandering spirits of the dead, or by the spirit of enmity, and he concludes that the causes are sometimes natural and sometimes supernatural.[1169] It is significant that, among so many theories framed by believers in the fact, there were so few who assented to the direct interposition of God.