6612. From all this it is also evident that the more exteriorly a man thinks, the less extension he has, and the more interiorly, the greater extension. For they who think exteriorly, that is, who are in what is sensuous, communicate only with grosser spirits; whereas they who think interiorly, that is, from the rational, have communication with angels; and the nature of this difference can be seen from the density of the sphere in which the sensuous spirits are, and from the purity of the sphere in which the angels of heaven are. This difference is like that between the extension of sound, and the extension of light; and how great this is, is known to those who are skilled in the things of nature.