I am quite prepared to admit what the Germans have called a night-side of nature--that is, various rudimental powers of doing many things of a seemingly miraculous character, which powers do very probably often co-operate in the production of spiritualistic phenomena, and under peculiar organic conditions, without any spiritual influence, may be brought into considerably developed action. Moreover, as it is, of course, in the investigation of these natural bases of magic that science will succeed so far as it succeeds at all, it is only right that it should expatiate in them. My complaint is that the modern attempt to reduce spiritualism to psychic force involves an inadequate analysis of the facts presented; and spiritualists have surely some ground to complain of the _prima facie_ disingenuousness of a manœuvre which, in regard to the same phenomena, began with, "This is not natural, therefore it is certainly not true," and ends with, "This is true, therefore it is certainly natural." However much the scientific mind of the day may dislike the preternatural stand-point, yet it may be that, seeing "an absolute and derisive incredulity" is no longer regarded as the one scientific attitude, some examination of the views entertained by Catholic writers on the subject may not be without interest. Many of the acutest amongst them for ages have given great attention to the phenomena of mysticism, although mainly engaged in the consideration of their moral and ascetical bearings. Before leaving this second hypothesis, I propose to bring together such passages from the schoolmen as seem to make the largest allowance on the side of psychic force. Whilst there are, I think, sufficient indications that the scholastics generally admit psychic force as a natural basis and concurrent cause in many of the phenomena of both divine and diabolic mysticism, it must be allowed that passages dwelling at any length on this point have at least the merit of rarity.