901. Besides the confirmations from heaven, other confirmations which are very numerous were also added from experience. When they kept the mind intent upon these they could understand that it is so, because the manifest experience before their eyes rendered it visible in a spiritual manner. But as soon as the experience and its life or intellectual light departed, they relapsed into their former state of ignorance and could not comprehend that such a thing is possible, and that it is life; for they suppose that merely natural lumen is light, though in itself it is darkness. To such spirits light cannot seem other than as darkness; but wherein that darkness consists and what its quality is can never appear except in light, that is, by those who are in light, the Lord alone giving enlightenment and making it manifest.* 1748, Feb. 21. * The entry in the index (s.v. Perceptio) has: "From darkness no one can see light; but from light darkness may be seen."