Revised August 23, 2022

For an introduction to consciousness, see “What is Consciousness?“.

1. When we look deeply into the issue of consciousness, we realize the unimaginable possible varieties of life. Let us start with the issue of dimensionality. Humans live in a four-dimensional world; in other words, humans are aware of four dimensions -three dimensions of space plus time.

Even though we used to think of time as being different from spatial dimensions, with his Theory of General Relativity, Einstein demonstrated that space and time are interrelated. He showed that the force of gravity could be explained as perturbations in the space-time fabric due to mass.
Can living beings exist in higher dimensions that we are not aware of?

2. Of course, we cannot even begin to imagine more than four dimensions (or more than three spatial dimensions). However, it is easier to think of and visualize the lower number of dimensions.

Imagine a two-dimensional creature living on your kitchen table. An ant will be the closest real example if we imagine that the ant cannot see above the table (a real two-dimensional creature would have only a length and width and no height). Now, if we put a hand on the table, the 2D creature could see part of the projection of the hand on the table. Now, if we take the hand off the table, as far as the 2D creature is concerned, the “hand” disappears; it cannot “see” any part of the hand if it is off the table, and thus it has no “awareness” of that hand existing anywhere. It does not exist in its “2-D universe”
For an amusing story of a 2D creature, see “Flatland: A Romance of Many Dimensions” by Edwin A. Abbott (2002). It was written in 1884 by Abbott, a mathematician.
Here is a “fun video” from Dr. Quantum which illustrates the idea:

3. Therefore, the “awareness” of the 2D creature on the kitchen table surface is limited to its 2D world. It is not aware of anything outside the surface of the table (if it is a “2D world,” the surface can extend to infinity, and as far as our 2D creature is concerned, it would not have “an end”). Furthermore, a 1-D world embedded in that 2D world would be a line on that surface. A 1-D creature in that 1-D world will not see anything that lies outside the line. Thus, the 2-D creatures can go in and out of the 1-D world by crossing that line!

Clearly, the consciousness of a 1-D creature is very limited, not necessarily by its mental capabilities, but by the dimensions of the “world” that it is in. A 2-D creature has an expanded consciousness compared to a 1-D creature. We in the 3-D world have even further expanded consciousness. (It must be kept in mind that one needs to incorporate the time dimension in all the above cases where only the space dimensionality was considered).

4. Therefore, if our world has more than three spatial dimensions, there may be other worlds we are unaware of since our consciousness is limited to the three spatial dimensions.

Thus, there may be beings in different dimensions that we are not aware of. We may be able to see “projections” of them if there is some overlap in 1, 2, or 3 dimensions. If there is no overlap, then we will not be able to see them at all, i.e., we will not be “conscious” of their presence.
For example, in the low dimensionality case we considered above, if a 2-D creature crosses over the “1-D line world”, the 1-D creature will see a “dot” when there is an overlap of the 2-D creature with the line. Yet, if the “1D world” lies above the tabletop, there is no overlap, and both creatures will not be conscious of the presence of each other’s worlds.

5. It is possible the “see” living beings other than humans and animals by developing certain jhānic (abhiññā) powers. Even before the Buddha, many yogis could access other realms and interact with such beings. One does not have to attain Nibbāna to do that, and some Arahants have not developed such powers. The Buddha discouraged people from interacting with such beings, particularly those in the lower realms.

“Our world” is much more complex than what is grasped by our senses, even though technology has enabled us to expand our consciousness; see “Expanding Consciousness using Technology.” Yet, we can expand consciousness even more by purifying our minds; see “Expanding Consciousness by Purifying the Mind.” A purified mind can see the truth in the Buddha’s wider world; see “The Grand Unified Theory of Dhamma.”
And our lives do not end with this one; see “Evidence for Rebirth.”
Those two facts constitute the basis of the true nature of existence and need to be thought about critically; one cannot comprehend the message of the Buddha until one at least has some idea about this “big picture.”

Next, “Six Kinds of Consciousness in our 3-D World“, ………..