But as we know not, and it seems even impossible that we should know by the light of reason, the nature and natural extent of the power of angels, demons, and disembodied souls, it seems that it would be rash to decide in this matter, as deriving consequences of causes by their effects, or effects by causes. For instance, to say that souls, demons, and angels have sometimes appeared to men—then they have naturally the faculty of returning and appearing, is a bold and rash proposition. For it is very possible that angels and demons appear only by the particular will of God, and not in consequence of his general will, and by virtue of his natural and physical concurrence with his creatures.
In the first case, these apparitions are miraculous, as being above the natural power of the agents in question; in the second case, there is nothing supernatural in them except the permission which God rarely grants to souls to return, to angels and demons to appear, and to produce the effects of which we have spoken.
According to these principles we may advance without temerity—
1st. That angels and demons have often appeared unto men, that souls separated from the body have often returned, and that both the one and the other may do the same thing again.
2d. That the manner of these apparitions, and of these returns to earth, is perfectly unknown, and given up by God to the discussions and researches of mankind.
3d. That there is some likelihood that these kinds of apparitions are not absolutely miraculous on the part of the good and evil angels, but that God allows them sometimes to take place, for reasons the knowledge of which is reserved to himself alone.
4th. That no certain rule on this point can be given, nor any demonstrative argument formed, for want of knowing perfectly the nature and extent of the power of the spiritual beings in question.
5th. That we should reason upon those apparitions which appear in dreams otherwise than upon those which appear when we are awake; differently also upon apparitions wearing solid bodies, speaking, walking, eating and drinking, and those which seem like a shade, or a nebulous and aërial body.
6th. Thus it would be rash to lay down principles, and raise uniform arguments, and all these things in common, every species of apparition demanding its own particular explanation.