the Edwardine Ordinal. Under the third head comes Spiritualism, which
we shall here not discuss in detail, but merely indicate certain
principles upon which it must be judged.

2. "There is nothing superstitious or unlawful in simply applying
natural agencies to the production of certain effects, of which they
are supposed to be naturally capable.... We must consider whether
there is a fair appearance of the cause being able to produce the
effect naturally. If there is, the experiment will not be unlawful:
for it is lawful to use natural causes in order to their proper
effects." (2a 2a, q. 96, art. 2, in corp., ad 1.) But this we must
understand under two provisos. First, that the "fair appearance"
spoken of be not opposed by a considerable force of evidence, whether
of authority or of reason, tending the other way: for in this matter,
which is not a mere matter of legality, it is not permissible to run
risks of becoming familiar with God's enemies. Secondly, that the
cause, though natural, be not morally prejudicial. Not even a natural
cause, brandy for instance, may be used to all its effects. Thus for
the mesmeric sleep, though that should be proved to be purely natural,
yet the weakening of the will thence ensuing, and the almost
irresistible dominion acquired by the operator over his patient,
render it imperative that such a remedy should not be applied without
grave necessity, and under an operator of assured moral character.

3. St. Thomas continues in the place last quoted: "Wherefore, if there
is no fair appearance of the causes employed being able to produce
such effects, it needs must be that they are not employed to the
causation of these effects as causes, but only as signs, and thus they
come under the category of preconcerted signals arranged with evil
spirits."