609. The three degrees into which the heavens, and consequently the human mind, are divided, can to some extent be illustrated by comparisons with materials in this world. The three degrees are like the degrees of nobility which distinguish gold, silver and copper; and there is a comparison drawn between them in the description of Nebuchadnezzar's statue (Dan. 2:31ff). The three degrees are distinguished as ruby, sapphire and agate are in purity and quality; and as the olive-tree, the vine and the fig-tree, and so on. In the Word too gold, ruby and the olive stand for celestial good, the good of the highest heaven; silver, sapphire and the vine for spiritual good, the good of the middle heaven; and copper, agate and the fig-tree for natural good, the good of the lowest heaven. I said before that there are three degrees, celestial, spiritual and natural.