Let us analyze what space is.
Take a basic element, a point, a one-dimensional object. When a point traces across a direction, it generates a line. Now, let us trace the motion of a line, a two-dimensional object. If it moves in the same direction as it is in, of course it will just continue to be a line. If it moves in a direction not contained in it, it traces a surface or a plane. Similarly, if a surface or a plane moves in a direction not contained in it, it will trace a solid, a three-dimensional object. So, a line is an infinite number of points. A surface is an infinite number of lines. A solid is infinite number of surfaces. Similarly, we can imagine a four dimensional space as an infinite number of three dimensional spaces.
Now, just as we built up these higher dimensions from the lower dimensions, we can also see the lower dimensions as parts or sections of a higher dimension space. For example, a point is the intersection of two lines. So, a point is a section of a line. A line is a section of a surface. A surface is a section of a solid. Extending this, we can say a solid is a section of a four-dimensional body. Our three dimensional space is a section of a four dimensional space.
P.D.Ouspensky, in his book Tertium Organum, explains these very beautifully. He extends this to say that many separate three dimensional bodies, like humans for instance, may actually be the sections or parts of one four dimensional body! He explains this with a simple example.
Suppose a horizontal plane intersects the top of a tree, parallel to the surface of the earth. Now, on this plane, the sections of branches seem to be all separate, not connected to each other. But, from the three dimensional space, we can see that these are all sections of branches of one single tree. In our four-dimensional world, the maximum dimensions in space can be only three. We can call this fourth dimension time. So, the four dimensional world can be looked at as a space-time continuum. It can be said that time is the fourth dimension of space.
We understand time in three forms – past, present and future. We think that the past is over and does not exist anymore. The future has not yet happened, hence it does not exist. The present thus happens at the transition of the non-existent future to another non-existence, the past. In the three dimensional world, we see that the seemingly separate sections of the tree in the two dimensional world are actually joined in the third dimension. In the same way, if we imagine a consciousness that can rise above our plane of living, this consciousness can also see the continuity in the fourth dimension of time with the past, present and future all existing simultaneously. This consciousness sees the simultaneous happening of events, which the ordinary consciousness sees as distinct events separated by periods of time.
A three dimensional body, moving in time, traces a four dimensional body. Across time, we can see the motion as we grow from a child to youth, to adult, to elderly person. But we are not able to see or feel this ‘four-dimensional body’ because of our limited perception. Being in the same three-dimensional world, we see only the section of the four dimensional body that is the normal three-dimensional body. It is like one of a series of pictures on a cinema roll.
To understand how a four-dimensional world is perceived in three-dimensional form, let us first see how a three-dimensional happening is seen in a two-dimensional world. Suppose you are in a two-dimensional world, the world of planes and surfaces. Your life, your perception is restricted to a plane, like a vertical wall. Now, imagine a wheel with each of its spokes painted in a different color is rotating perpendicular to the plane in which you live. How will you perceive the motion of this wheel? When a spoke of the wheel intersects the plane, you will see a line of a certain color at the intersection of the wheel and the plane. Then, after one spoke passes, there will be a gap when you will not see anything. Then, the next spoke of a different color will pass through the plane. So, you will perceive the motion of the wheel as lines of different colors happening at regular intervals of time.
What is happening is this, the limited perception in a lower dimensional world is changing the perception of space to a phenomenon in time! Since you can see only two of the three dimensions of space, you see the third dimension only when it becomes manifest on your plane over time. Hence, you see it as unrelated to your two dimensions of space, and you call it a phenomenon in time. Now, imagine when a green spoke passes through the plane, simultaneously another independent phenomenon occurs, say the barking of a dog. In the two dimensional world, it will be seen as a correlation between the appearance of the green line and the sound of a dog barking, when in reality it is not! It is not possible for the two-dimensional being to believe that there can be a rise of events outside his plane of perception. That means, to understand the three-dimensional world, he cannot be in the two-dimensional consciousness, he has to rise to the three-dimensional consciousness.
Similarly, to understand the four-dimensional world, we have to be in the fourth-dimensional consciousness. Is this possible? Is it possible for us to go beyond the perception of the senses which give us only a three dimensional view? Can we actually see reality instead of mere glimpses of reality as phenomena in time? The answer is YES. Through in-depth research and development, the Eastern mystics and sages have discovered that it is possible to understand Reality as it exists and to experience it also. This can happen as a natural way of life, not just as a chance happening. This experience has happened in them. Through meditation, it is possible for us to experience this same state of awareness.
A beautiful Zen story:
Once, two soldiers were looking at a flag flying in the wind.
One of them said, ‘The flag is moving.’ The second one said, ‘No, it is the wind that is moving.’ A Zen master passing by saw the argument going on. The soldiers requested the master to help them resolve this serious issue.
One of the soldiers asked, ‘Master, I say the flag is moving. But he says the wind is moving. Which is correct?’ The master says, ‘Neither is correct. Only consciousness is moving.’
As of now, what we feel as reality everyday of our life is also a ‘virtual’ reality. It is only a perception of things being separate in space and time. If you look deeply, you can see how our very perception of the world itself is questionable. From whatever quality of consciousness we see, that appears as our reality, not the absolute Reality.
source: Living Enlightenment