of the
spirit to be established? This question of discerning spirits, of
identifying them, of not taking an angel for a devil, or vice versa,
was most important in the Middle Ages. On this turned the fate of
Joan of Arc: Were her voices and visions of God or of Satan? They
came, as in the cases mentioned by Iamblichus, with a light, a
hallucination of brilliance. When Jean Brehal, Grand Inquisitor of
France, in 1450-1456, held the process for rehabilitating Joan,
condemned as a witch in 1431, he entered learnedly into the tests of
'spirit-identity'. {66a} St. Theresa was bidden to try to exorcise
her visions, by the sign of the Cross. Saint or sorcerer? it was
always a delicate inquiry.

Iamblichus, in his reply to Porphyry's doubts, first enters into
theology pretty deeply, but, in book ii. chap. iii. he comes, as it
were, to business. The nature of the spiritual agency present on
any occasion may be ascertained from his manifestations or
epiphanies. All these agencies show _in a light_, we are reminded
inevitably of the light which accompanied the visions of Colonel
Gardiner and of Pascal. Joan of Arc, too, in reply to her judges,
averred that a light (claritas) usually accompanied the voices which
came to her. {66b} These things, if we call them hallucinations,
were, at least, hallucinations of the good and great, and must be
regarded not without reverence. But modern spiritualistic and
ghostly literature is full of lights which accompany
'manifestations,' or attend the nocturnal invasions of apparitions.
Examples are so common that they can readily be found by any one who
studies Mrs. Crowe's Night Side of Nature, or Home's Life, or
Phantasms of the Living, or the Proceedings of the Psychical
Society. Meantime Homer, and Theocritus in familiar passages,
attest this belief in light attendant on the coming of the divine,
while the Norse Sagas, and the well-known tale of Sir Charles Lee's
daughter and the ghost of her mother (1662), speak for the same
belief in the pre-Christian north, and in the society of the
Restoration. {67a} A light always comes among the Eskimo, when the
tornak, or familiar spirit, visits the Angekok or sorcerer. Here,
then, is harmony enough in the psychical beliefs of all time, as
when we learn that lights were flashed by the spirits who beset the
late Rev. Stainton Moses. {67b} Unluckily, while we have this cloud
of witnesses to the belief in a spiritual light, we are still