38. A particular effect of this kind of phenomena is, that the vaporous and even tangible apparitions are indistinctly perceptible to everybody. The spirits show themselves only when they desire, and to whom they desire. A spirit would then be able to appear in an assembly to one or more persons, and not be seen by all. This is because these kinds of perceptions are processed through the spiritual, rather than the corporeal vision. Accordingly, spiritual visions are not awarded to everyone, and the communicating spirit can, at his exclusive discretion, if necessary, disable it in those whom he does not wish to be seen by. Likewise it can, momentarily, be awarded to someone, if the communicating spirit deems it necessary.
The condensation of the perispiritual fluid of apparitions, extending even to its tangibility, lacks the properties of ordinary matter. If it were not so, apparitions would be perceptible through the corporeal eyes, and thus perceived by everyone present. *
* We must be very cautious in accepting as facts strictly individual recitals of apparitions, which in certain cases may have been the effect of an over-excited imagination, or an invention for some selfish end. It is well, then, to gain a careful account of the circumstances, of the respectability of the person, as well as the interest they might have in abusing the credulity of too-confiding individuals.