Question Three of Chapter Three of the Third Decade
Whether a demon can move bodies by the command of the will alone
It is asked whether demons can move bodies without approximation, by the command of the will alone.
To this it is answered thus: since corporeal nature, as has been said, stands in obediential relation under the ordinary influx of God—especially, as Augustine says, with respect to local motion—in relation to the command of the free will of angels, there is no doubt that good or evil angelic spirits can move the body, organs, and muscles with which they are united coexistentially through their essence.
Hence the philosophers conceive that unless an intelligence really coexisted with an orb or a part of it, it could not move that orb.
But the doubt here is whether good and evil angels can move bodies through intellect and the command of the will without such approximation.
For, if so, it follows that a demon existing far outside a human body could move that body and its parts locally at pleasure. Indeed, while remaining in hell, it could equally disturb or move by its command the animal spirits in the human imagination, which in no way appears to have been conceded to good or evil angelic spirits.
To this it is answered that, although corporeal nature obeys the command of spirits with respect to local motion, this must nevertheless occur with a limitation to some determinate union or presence of those spirits to the bodies which they wish to move.
Beyond this, it is necessary to concede that they possess the power of immediately introducing alterative qualities—namely heat, cold moisture, and dryness—and likewise qualities which cause local motion, such as impetus, impulse, and other motive qualities.
In this way all the effects of spirits which they produce and have produced in the transmutations of corporeal things are fittingly accounted for through those qualities.
For how otherwise would they raise storms so suddenly, as is related in Job, chapter 1?
How would they produce marvelous apparitions and marvelous transmutations of things?
How would they cast a stone from a distance except by the command of the will, causing motion in the stone through impetus or impulse?
This is evident in the flint stone of marvelous spherical form which the devil cast over the head of the holy Father Dominic while he was praying in Santa Sabina in the city. But, because God prevented it, the stone did not touch the saint; the stone hangs there as a memorial.
How could a spirit be united to some body in such a way that the body would be moved accidentally with the exceedingly swift motion of the angel?
To the doubt it is therefore said that a demon can move bodies and souls, not without qualification, but with a limitation to some determinate union or presence of the spirits themselves, as has been said.
All these things are from Henry of Assia upon Genesis.