90. Because angels are spiritual, they can live in no other heat or light than in that which is spiritual. Men, however, can live in no other heat and light than in the natural, for spiritual [heat and light] suit the spiritual, and natural [heat and light] suit the natural. If an angel were to draw the least thing from natural heat and light, he would perish, for it is entirely unsuitable to his life. Every man, as to the interiors of his mind, is a spirit. When the man dies, he goes forth from the natural world altogether, leaving everything of it, and comes into a world in which there is nothing of nature. And in that world he lives thus separated from nature so that no communication takes place by continuity, that is, as of purer and grosser but as of prior and posterior, which communication is only possible by means of correspondences. Hence it can be established that spiritual heat is not a purer natural heat, nor spiritual light a purer natural light, but that they are altogether from another essence, for spiritual heat and light derive their essence from the Sun which is pure Love and Life in Itself, and natural heat and light derive their essence from a sun which is pure fire in which there is absolutely nothing of life, as was said above.