Today's post is a continuation of my work into developing a planar model as an extension of the mystic class/psionics system I'm working on for BX/LL.
yesterday's post digging into the history of planar concepts (as an extension of the mystic class/psionics system I'm working on for BX/LL), today's chart is from the 1925 book A Treatise on Cosmic Fire by Alice A. Bailey. Like Mr. Leadbeater, Ms. Bailey was a theosophist/esoteric philosopher. Also like Mr. Leadbeater, Ms. Bailey suggests the lowest three planes are physical: 1) solids, 2) liquids, 3) gases; and that the next four planes are etheric. From there, Ms. Bailey's planes seem to coincide with Mr. Leadbeater's, with some Western additions to the Eastern naming...
So, at this point, I'm still thinking that...
1) Access to other physical planes from the prime material plane (that is, to the positive material, negative material, elemental planes, etc.) will be through the ethereal plane.
2) Access to the astral plane will be through the ethereal plane. (See this post at Delta's D&D Hotspot, and the comment thread, for discussion of early editions, and whether the astral plane was accessed through the ethereal plane, or accessed directly, from the prime material plane.)
3) Access to the higher planes will be "up" through the "upper" ethereal plane to the "upper" astral plane.
4) Access to the lower planes will be "down" through the "lower" ethereal plane to the "lower" astral plane.
5) Moving to the outer edges of the physical plane accesses the "dreamlands"; moving "up" from the dreamlands access deep dreams, and moving "down" from the dreamlands accesses nightmares. (This is a concept I'm adapting from Steve Marsh's current model of the planes... but that's a whole 'nother post.)