One alone

Let us begin with the premise that One alone exists.

This means that there is only One. There is never in any sense two or more.
That means there cannot be a self and the world. For that means two separate things, self and world.

Thus, the One is neither the self nor the world.

That One must be formless. For form implies boundary, hence two i.e one inside and other outside.

Thus, the One is absolutely without form. Neither physical nor mental form.

There is thus no perceiver, no witness, no perceived.

Since there is no perceiver, there is nothing to perceive. Hence no space.

Can it have time then?

Time implies a consciousness of past. A sense of the passing of moments. A sense of memory of having a previous existence. Hence by inference, a future existence. If there is a sense of past, i.e memory of previous existence. Infact, the absence of time cannot even be conceived. For any conception requires time. But, if there is only One and time as well, then there must be memory as well. But since there is only One, there cannot be memory. Hence there is no time. Hence no conception of beginning and ending. Since there is no memory, there is no identity. Since there is no time, there is no change. Hence there is no cause and effect. There is hence no creation. No experience.

At this point, it becomes difficult to go further. The One is pure existence itself. Absolute presence. With no conception of any identity, past, or concept. No cause. No self. Absolute doubtless existence.

Time and space can only exist outside it, yet there is no outside. Thus time and space are mere illusions. Having no reality. Only appearances which appear real only in ignorance. There is no cause for the appearance of time and space and the notion of a self.