Felt inclined to share some of my past ideas and debates on reality in general I've recently reiterated and compiled.
Though it should be stated I don't believe any of these ideas presented as necessary truth, I did at one point.
Coming from a non-religious dominated perspective, concepts of the beginning of reality don't necessarily demand a linear foundation.
*Time itself, if even believed in, can theoretically be granted an endless array of dimensions. Applying that which define our first three dimensions, to the fourth current understanding of time: Linear time could be looked upon as 1 dimensional. The belief in the possibility of time that breaks off into other paths, not one fixed, but endlessly multiple seemingly linear (or perhaps eventually non-linear, or contrary) foundations which stem from a number of factors involving possibility could be looked upon as an added second dimension.
The third dimension added to this construct of time, could be looked upon as realities that are foreign to all that is currently conceivable, existent in a sense, but so far removed from any resonation of reality we are capable of detecting, despite possibly being influenced, or unknowingly existent in this facet of reality, as well as having multiple selves in the second dimension in this model.
Currently, we would seem to be propelled only forward in linear reality, but eventual evolution could theoretically allow us to dominate the others mentioned in this model, including consciously existing in multiple versions of realities, as well as our essence manifesting in other alien resonations.
This would obviously also include an ability to travel throughout previous time constrained linear realities.
Adding a fourth dimension to the model of time could imply something that would eventually allow itself conception as we progress. Again, this is all just speculative fun, though I did hold firmly to this understanding at one point in time, despite it demanding some founding belief in what is defined as 1D, 2D, 3D and even 4D.
While we can look at the material, tangible aspects of "reality" as building blocks upon that which is real. At what point does conception dictate itself as a definitive justification of what it appears to conceive? How are multiple conceptions of a perceived similar state in reality enough to form that which is real? Especially since one seems incapable of actually being able to perceive another's reality as unified with one's own, aside from interaction with another, which in and of itself could just as well be illusion.
There would seem to be no foundation aside from bias that can dominate enough to become definitive reality that goes beyond ones own personal understanding.
Just what is tangible reality when taken into consideration, and how is that which is intangible non-existent? Intangible could easily be looked upon as a facet of reality that currently escapes our current conception. Therefor, intangible as a basis to extend an opposite capable of justifying tangible as a manifestation of truth can also be debated.
Assuming the universe to be infinite, it would seem logical that within this endlessness, there is room for an infinite number of possibilities. One of these possibilities would therefore be that the universe is finite, or both finite and infinite, or neither, or both and neither. In fact, belief in a universe of infinite possibilities would inevitably imply that there is no universe at all.
Though infinity in and of itself is still a concept that seems to allude any manner of containing conception. The fact that it is even vaguely conceivable could be looked upon as basis enough to consider it when given the popular trend of belief. Believing there is no start or finish also seems to lean toward a belief in infinity, or an endlessness.
The "fact" that one could break down anything into an infinite number of pieces can also, following a strain of logic, imply that one can extend reality indefinitely, as well as limit it finitely, and gives rise for the possibility of both being true.
The idea of thought, a realm of concepts, dreams and such as being more than just ones own personal conceptions, but becoming aware of another form of reality that would still differentiate itself form even more than a collective conscious, or unconsciousness is also an enjoyable idea to toy with.
Thought that is currently experienced within ourselves could be looked upon as the formation of a new manner of manifesting, beyond that of matter, losing the bodily "machine" so to speak. Though in appearance, much more sci-fi and less likely, thought could even be a "bridge" that is manifesting to unite us with another, currently unknown or vaguely understood form of reality. "Another dimension" so to speak.
Perhaps I'll expand upon this at a later time.
*When I first began toying with this idea I didn't draw an apparent difference betwixt the obvious semantic jumbling of the definitive first three dimensions with the unrelated inclusion many dub the 4th dimension. Though to present some form of more logical correlation between time and the other axis based perception would simply be applying a fixed, founding concept to another mold (in this case, axis based perceptual dimensions to the concept of time,) assuming it universal in some sense.