Now, surprisingly enough—in spite of their disparity—these two alleged psychic structures, Freud's and Jung's, can be combined into a more complex structure that, as we will see (again, in Up The Garden Path), has some amazing implications for literary allusion. In this combined structure, which we call the Psychic Octahedron (as shown on the right), Jung's Horizontal Cross forms the four horizontal corners of this double-pyramid shape (which is known mathematically as an octahedron), while Freud's vertical axis lends its end-points to the zenith and nadir.
Of course, the octahedron itself reflects the three-dimensional shape of real space; and as such it was one of the most important religious symbols of the ancients. For this reason alone, it is of great value for the well-informed rhetor.