problems concieving extension
Concieving of the physical as that which has extension in dimensions of space, we can also concieve of the mental as having the property of extension in time.

Illssuiary, it may or may not be, the sense of extension in time is an essential quality to the experience of being alive. As consciousness requires "something" to be conscious of, that "something" is neccessarily a changing of states of a "thing"/"One" who is experiencing that change, of which his experience is constituted.

So there is always a kind of temporal projection, or time lag of the senses, that is aware of the changing-ness of the state of the physical body. And this is where/what the mind exists in.

(Imagine a sea of infinite dimensions, all containing hypothetical straight lines. These lines have existence by virture of their intersection with eachother, creating various axese, of what for 2-D has infinite potential extension, and for more dimensions can contain confined spaces, such as shapes. And size comes about by virtue of the relative sizes of the variety of shapes with eachother. There is no neccessary reason why any actual shape would form, but the information of the intersection of the lines (the angles at the points) relative to the primary intersection of infinate extension would create, if not definate shapes, a spiraling space, of continuously varying relative length yet consistent angel change, hence a spiraling, that may vary from large to small, to large again, and so on.)

The question of the difference between time as a dimension, and space as a dimension is crucial however.

Also remains, the possability, at the very least, of the eturnal reccurence, in the respect of however awareness of time might be total illusion, or might, at least by virtue of the mathamatical laws that (supposedly constant) make up the physical objects of experience that are experienced as persisting in time, that the material form of experience, supposedly represented by systems of electrons, being as the projection of a physical/mathamatical order changing in some respect, as that mathamatical order will repeat. And with that repetition so too the time perception/extension. And even if time perception is only utilisable by living animals, it , as an arrangement of electrons, or as any other demonstration of material properties will persist, possibly continueously, possibly over and over again, possibly be re-lived by other living creatures, as karma.

The mirrors of time.

But what are the dimensional spaces, the substance of the lines, the forms of extension?

forms are surely required for extension to exist.

the idea of something being double, or any ratio of an origional limit of extension would seem non-sensical....the value of 1 is undetermined.

some kid of quantification takes place, even if we imagine form to exist, without extension, and extension to exist out of relative forms.

if extension is in any way fixed, if we can concieve of it being fixed, the we can imagine differences being generated out of the forms, existing by virtue of the information of their specific number/ degree of angle, and its repetition in constituting an entire shape, and thereby being objectively defined/"eturnal".