Arnald and the Inquisition.
Already during Arnald’s lifetime in 1305 the inquisitor of Valencia forbade the possession or reading of his books, a decree against which King James protested. Five years after Arnald’s death the inquisitor and provost of the church at Tarragona declared some statements in Arnald’s writings heretical, and Diepgen thinks that we have lost a number of his religious writings in Catalan in consequence;[2686] but this sentence appears to have no more lessened his medical influence than his trial at Paris had prevented his having intimate relations with the popes.
His works.
One indication of Arnald’s long continued influence in the learned world is that some seven so-called complete editions of his works were printed in the course of the sixteenth century.[2687] Besides this, some of his writings were published separately or appeared in miscellaneous collections, and some were translated into the vernacular languages. Some, however, still remain in manuscript form. The majority of his writings are medical, such as the Mirror of Medical Introductions, Breviary of Practice, Rule of Health, General Rules for the Cure of Disease, Commentary on the Regimen Salernitanum, Collection of Antidotes, and special treatises on the stone, gout, and epilepsy. But besides the works of alchemy ascribed to him there are other treatises on themes of especial interest to us, the Disapprobation of Sorcerers (Libellus de improbatione maleficiorum), Remedies against Sorcery, Judgments of Infirmities by the Motion of the Planets, and the treatise on Seals or astrological images. Although Arnald interpreted dreams for kings, the treatise on interpretation of dreams which is printed with his works is in the manuscripts either anonymous or ascribed to William of Aragon. Some of these other works too are perhaps not by him, but similar themes are occasionally touched upon in his more purely medical works. In the printed editions of his works is found a Latin translation of the treatise of Costa ben Luca On physical ligatures, which we have already discussed, and it is not unlikely that some of the aforesaid works are translations from the Arabic and not original compositions by Arnald. Some of his medical writings seem little more than repetitions of Galen, whose works he cites a great deal.
His attitude to natural science.
In one of his medical works Arnald states that the proverbs of Solomon show that what learned men have revealed in the world of nature can be adapted by convenient metaphor to moral instruction. But from this one should not jump to the conclusion that he thought that the chief use of natural science was to point a moral. On the contrary in almost the next sentence we find him affirming that “all true knowledge arises from the senses” and that the education of youth should begin with this sense knowledge, “graciously and efficiently demonstrated.” Thus Arnald would assign to natural science a leading place in education. As the mind went over this material, he thinks that it would reach many abstract conclusions, and could gradually attain “to the knowledge of insensible and occult and arduous and subtle things, as is illustrated by the whole course of theology and by the whole course of medicine.”[2688]
Magic excluded from medicine.
There are passages in Arnald’s works where, like Pliny, Galen, and other writers since them, he professes to exclude everything savoring of magic and superstition from his medicine. For instance, in his chapter on Those things whose use is permitted in the cure of epilepsy, a disease into whose treatment we have seen that magic is especially liable to enter, he would “repel the ignominious” enchanters, conjurers, and invokers of spirits, diviners and augurs, from the field of medicine as a godless crew who are servants of the devil. He cites the church fathers to show that all pagan divination is by demon aid. In the same chapter he disapproves of any use of “characters and superstitions” in medicine, and even forbids the use of the sign of the cross or Lord’s Prayer in collecting medicinal simples.[2689]
Disapprobation of Sorcerers.
In his Libellus de improbatione maleficiorum[2690] Arnald questions the power of sorcerers or necromancers to invoke demons and compel them to give responses or to work wonders. By adopting a very similar argumentation to that of the early fathers he arrives at the familiar theological conclusion that men are purposely misled in these arts of sorcery and necromancy by the demons who have invented the fiction of an art and a procedure to cover their own iniquitous ends. Arnald is not concerned to emphasize this conclusion especially, however; his object is rather simply to show that demons cannot naturally be compelled by man to obey him. He argues that the human mind, which is joined to a body, is of inferior grade to separate or incorporeal substances and so cannot command them. He also holds that demons who are spiritual beings cannot be coerced by human use of natural objects such as gems or even by human use of the influence of the stars. He denies that demons are distributed in any particular quarters of the heavens, or that they are subject to man at any particular hours of the day. He denies that spirits can be coerced by the light of the celestial bodies, asking, if this is so, why they are invoked at night and in darkness rather than at midday. He admits that it is the opinion of many that a spirit can be coerced by the special virtue of Saturn or of Jupiter or some other star; but he questions whether man can master this special virtue of a planet, “since no terrestrial substance naturally governs a star, although some philosophers have said that the human soul sometimes commands the nature of the elements.” He also raises the familiar objection that the invokers of spirits are usually inferior to other men in virtue and intelligence, whereas those who lead pure and rational lives should by rights be the ones to control the influence of the stars, if any men can. Arnald further denies that artificial figures and characters or words uttered by man can overpower demons, since these artificial products derive such virtues as they have from things of inferior nature or the stars or the human artificer, and he has already insisted that none of these can coerce spirits. He justly observes that to contend that necromancers can control the demons through superior demons is “stupidly said” and begs the question. He therefore concludes that God alone can control the evil spirits and that He would delegate His power, if at all, only to saintly men and not to such wicked sinners as the invokers of demons are. The Histoire Littéraire de la France, in its brief account of this treatise, says, “It goes without saying that Arnald does not think all sorceries purely imaginary; however, it should be stated that he tries to demonstrate that demons are less at the beck and call of sorcerers than is commonly thought, and that many so-called instances of sorcery are merely pathological cases.” This last has reference to the close of the treatise where Arnald makes the commonplace medieval observation that persons suffering from melancholy are to be humored in their delusions.