It is also said to consist of a finer substance, more pure and composed of smaller particles, than the ordinary matter of the physical plane.
Leadbeater) The English term "etheric" in this context seems to derive from the Theosophical writings of Madame Blavatsky, but its use was formalised by C.W.
The intended reference is therefore to some extremely rarefied matter, analogous in usage to the word "spirit" (originally "breath").
In selecting it as the term for a clearly defined concept in an Indian-derived metaphysical system, the Theosophists aligned it with ideas such as the prana-maya-kosha (sheath made of prana, subtle breath or life-force) of Vedantic thought.
In 1774, August Wilhelm Hupel wrote about the soul being composed from an etheric type of matter.
[10][11] He states that in the second Initiation of Fire, which is reached through working with sexual magic with a spouse, the Kundalini rises in the vital body.
Then the initiate learns how to separate the two superior ethers from the others in order for them to serve as a vehicle to travel out of the physical body.
[18] Susan Blackmore has raised various objections to the idea of an etheric body, noting that "it is not much of a theory to argue that the double is material, and can do all the things required of it, yet is invisible, undetectable, and consists of some kind of matter we know nothing whatever about.