167. As the light of heaven has now been spoken of, something must also be said about the light of hell. This also is of three degrees: light in the lowest hell is like that of burning coals; light in the middle hell is like that from the flame of a fire on a hearth; and light in the highest hell is like the light from candles, and to some like the light of the moon by night. These lights are not natural but spiritual, for all natural light is dead, and extinguishes the understanding; and those who are in hell have the faculty of understanding, called rationality, as has been shown before; and rationality itself is from spiritual light, and not at all from natural light; and the spiritual light which these have from rationality is changed into infernal light, as the light of day to the darkness of night. [2] Nevertheless, all in the spiritual world, both those who are in the heavens and those who are in the hells, see in their own light as clearly as man by day sees in his. The reason for this is that everyone's eyesight is formed for the reception of the light in which it functions. Thus the eyesight of the angels of heaven is formed for the reception of the light in which it functions, and the eyesight of the spirits of hell for the reception of their light; and this, to use a comparison, is as sight with night birds and bats, which see objects at night and in the evening as clearly as other birds see them by day, for their eyes are formed to receive such light. [3] The difference, however, between these lights appears very clearly to those who look from one light into the other; as when an angel of heaven looks into hell he sees nothing there but merely thick darkness; and when a spirit of hell looks into heaven he sees nothing there but thick darkness. The reason of this is that heavenly wisdom is like thick darkness to those who are in hell; and, on the other hand, infernal insanity is like thick darkness to those who are in heaven. From these circumstances it may be evident that the light a man has is such as his understanding is; and that after death everyone comes into his own light, for he does not see in any other. Moreover, in the spiritual world, where all are spiritual even as to their bodies, the eyes of all are formed to see from their own light. The life's love of everyone makes an understanding for itself, and so also a light; for love is like the fire of life, from which is the light of life.