609. The three degrees in which the heavens are, and consequently, in which the human mind is, may also be illustrated in some measure by comparisons with material things in the world. In their relative nobility these three degrees are like gold, silver, and brass, to which metals they are likened in the statue of Nebuchadnezzar (Dan. 2:31-35). These three degrees are also distinct from each other, like the ruby, sapphire, and agate in respect to purity and goodness; also like the olive tree, the vine, and the fig-tree; and so on. Moreover, in the Word, "gold," "ruby," and "oil" signify celestial good, which is the good of the highest heaven; "silver," "sapphire," and "a vine" signify spiritual good, which is that of the middle heaven; while "brass," "agate," and "a fig-tree" signify natural good, which is that of the lowest heaven. That there are three degrees, a celestial, a spiritual, and a natural, has been stated above.