Aether

Aether is one of the six primary substances of existence, alongside matter, energy, time, information, and magic. It is most commonly found in a discrete packet (called a soul) associated with the essence of some other thing. Aether and matter are seen as analogous substances, to the point that some argue aether is not a primary substance at all and is instead a fifth, sixth, or seventh element alongside water, earth, fire, air, wood, and/or metal. Aether, however, violates the conservation law that matter follows, and since the old element systems have fallen out of favor in contemporary natural philosophy, a five-substance model without aether seems insufficient to explain the structure of existence.

Properties

Material Characteristics

Aether is invisible and intangible to most creatures in baseline conditions.
When made visible in some manner, it typically appears to be a translucent, light-blue, and somewhere between flame and fluid in texture and in the nature of its constant shifting.
When made tangible in some manner, it feels impossibly light, and it has no identifiable texture — akin to touching smoke. Even tangible aether can be passed through as though it wasn't there, so long as the creature passing through wishes to be unobstructed. Aether seems to always be at a comfortable temperature when touched, even if the definition of "comfortable" varies between two simultaneous observers.

Physical & Chemical Properties

Aether is not subject to conservation. It can be created from nothing, and is self-propagating. "Active" aether gradually produces more aether. Souls are comprised of active aether, meaning that anything with the capacity to convert aether into energy can use a soul as an infinite energy source. However, a soul is not an infinite power source, because the soul can be destroyed if the energy draw outstrips production and the last traces of aether are used up.
Aether can overlap itself to a seemingly infinite extent without a noticible increase in density. This makes the substance incredibly difficult to measure.

History & Usage

Everyday use

Aether can store information, which is what allows souls to "copy" the minds of their owners. Aether readily converts into magic when directed to, and since magic can circumvent natural laws, this allows the creation of new matter or energy, and to a much lesser extent new time.

Type

Metaphysical