The question of the angels and spirit beings is one of those questions in which the reality of a universal may be inferred from the existence of a single particular. If a single individual is seen, the existence of the species may be concluded. Whoever denies it, denies it as a member of the species to which it belongs. While whoever accepts the single individual is compelled to accept its whole species. Since it is thus, consider the following:
Have you not seen and heard that all the scholars of the revealed religions throughout the ages from the time of Adam until now have agreed on the existence of the angels and the reality of spirit beings? The different groups of mankind have concurred in having seen and conversed with angels and in their narrations concerning them, as though they were discussing and narrating events about one another. Do you think that if a single angel had not been seen, and the existence of one or numerous individuals not been established through observation, and their existence not been perceived clearly, self-evidently, that it would have been at all possible for such accord and such a consensus to continue, and to continue persistently and unanimously in such an affirmative and positive manner, based on observation?
Also, is it at all possible that the source of this general belief should not be some necessary principles and self-evident matters? And is it all possible that a baseless delusion should persist and become permanent in all the beliefs of mankind throughout all the revolutions it has undergone? And is it all possible that the basis of the assertion of these scholars of the religions, of this mighty consensus, should not be a certain intuition and empirical certainty? And is it at all possible that that certain intuition and empirical certainty which result from innumerable signs, and those signs which have been observed on numerous occasions, and those numerous observations should not all, without doubt or hesitation, be founded on necessary principles? In which case, the cause and the basis of the assertion of the universal belief held by these scholars are the necessary and categorical principles resulting from the great number of times the angels and spirit beings have been observed and seen, which demonstrates the strength of the consensus.