5. Ultimate Reality: Known Unknowns and Unknown Unknowns

“There are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don't know we don't know.”

― Donald Rumsfeld

“Perception is not a window on objective reality. It is an interface that hides objective reality behind a veil of helpful icons.”

― Donald D. Hoffman, in “The Case Against Reality: Why Evolution Hid the Truth from Our Eyes”

Morpheus: “What is real? How do you define 'real'? If you're talking about what you can feel, what you can smell, what you can taste and see, then 'real' is simply electrical signals interpreted by your brain."

― Lana Wachowski, in “The Matrix: The Shooting Script”

The Rumsfeld Matrix of Ultimate Reality!

Ultimate Reality is the name we give to the most fundamental reality that exists. Sometimes we use other words for it, like “existence” or “the fabric of reality” or even “the ultimate truth”.

And, just like some of the quotes above suggest, it is unknown to us. All we know are the electrical signals reaching our nervous system, and any inferences we can make from them. We have no way of knowing what is generating those signals.

We could very well be in a simulation, as many people believe, and have no way to tell.

In fact, as the Rumsfeld quote above says, not only do we have many known unknowns about ultimate reality, but we also have an unknown number of unknown unknowns.

Among the deepest known unknowns of reality are questions such as:

  • What exists? In particular, what exists "out there" and "in here"? (And what does "out there" and "in here" even mean?)

  • Why does it (or anything) exist at all? Where did it come from? (And if it did come from somewhere, where did that come from?)

  • Does existence have a beginning or an end? What came before? What happens in the end?

  • What does “existence” even mean?

  • We call everything we can perceive using our senses, such as vision or hearing or touch, as "physical". But what does “physical” even mean?

  • Is this physical reality different from our ultimate reality? In that case, how does the former emerge from the latter?

  • What is "experience"? What is consciousness? How does that emerge?

We have asked these questions for eons. And while we have made tremendous progress in answering so many questions, we haven't really answered any of the questions above convincingly.

And of course, beyond this long list of "known unknowns", we also have the, possibly never ending, list of "unknown unknowns". And for them, since we don’t know what we don’t know, we can’t even ask any meaningful questions about it.

In spite of all these difficulties, thinking about our ultimate reality has occupied the minds of many thinkers for millennia and their thoughts have formed the basis of many religions, philosophies and cultures.

So much so, that we have come to believe that unless some body of knowledge, like a religion or philosophy has answers to these questions, that body of knowledge can’t really say anything about things like meaning, purpose and hope.

This is because, for a long time, we have believed that there was some omnipotent and omniscient entity behind all of reality, that created it and had its own reasons and plans for it. The belief was that concepts like meaning, purpose and hope have their origins in those reasons and plans.

But, as I mentioned in the previous chapter, we have no need for that hypothesis.

What I am claiming in this book is that we do not need to find ultimate answers to the “unknowns” mentioned above in order to come up with rigorous, evidence-based definitions of meaning, purpose and hope. We can absolutely get there by relying on just the “knowns”.

Yes, once again, we are talking about our methodology of Mindful Bounded Rationality.

Mindful Bounded Rationality to the Rescue

As we have already mentioned in the chapter on Methodology, we do not need to start from “why does anything exist at all and where did it come from” etc., and having to rely on some supernatural power to rescue us from that conundrum.

We also do not need to start from some distant past when the universe “began” or some distant future, when the universe will supposedly “end”. Both of those events are so distant that there is a lot of uncertainty about those events as well as the path we have taken from there to here or from here to there, respectively.

Instead, we will start from what we know a lot more about: We will start from entities and processes that can be shown to exist right here, right now.

Think of existence not as a story of the universe from the beginning to the end, with both ends shrouded in mystery. Instead, think of it as a story that begins with you at the center, where things are quite crisp and clear, but they get foggier and foggier as you move away in time or space in any direction.

Needless to say, you have a lot more evidence supporting the idea that you exist here and now, than about how the universe may have been created or how it will end.

You are conscious, you are breathing, you can see and feel things happening around us. You know where you are in relation to your surroundings. You are aware of your thoughts.

This is basically how the Mindful Bounded Rationality approach to solving problems works. We don’t ask for the entire universe to be completely unveiled to us, we make do with what we know far more clearly, and see if we can get to where we want to go from there.

So, what do we know about the here and now?

We know three things for sure:

  1. Something seems to exist, including us. That is pretty much all we know about the ultimate reality because, as far as we know, we don’t have direct access to it. All we have are our perceptions that we can sense using our nervous system. This brings us to the next point.

  2. We seem to have a physical existence, in something we can call Physical Reality. We know this because we can perceive it, but we don’t really know how this physical reality emerges from the ultimate reality. But that's not all we have.

  3. We also seem to have a conscious existence. We are aware of our existence and our physical reality through our consciousness. We clearly have a sense that there is some presence inside of us. We don’t know how our consciousness emerges from the ultimate reality or whether it has any relation to physical reality either. (Yes, there are some speculations about that, but none of them are proven. We will look at some of them later.)

Unfortunately, even these simple statements of fact lead to raging debates.

Philosophical Debates

Most people take our physical reality as the primary reality, and consciousness as secondary. This is generally known as Physicalism or Naturalism.

Other people object to that and say that true reality is ultimately non-physical, and consciousness is all that there is. For them, it is physical reality that is secondary or emergent or even imaginary. This idea is closely related to the philosophy known as Idealism in the west and Brahman in Vedic Philosophy or Tao in Chinese Philosophy.

Unfortunately, we have no objective and incontrovertible proof of either of these two claims. This causes endless debates and confusion about which model is “real”.

We do not need to get into that debate.

Our methodology of Mindful Bounded Rationality tells us that we have no need to get into these abstract debates. Instead, we need to focus on grounding ourselves into the here and now, and with our ultimate goal in mind.

We don’t need our answers to originate from some supernatural power or from some “beginning of time” or some “judgment at the end of time”. We are fine with looking for answers in the here and now.

Also, as with all of science and engineering, we are fine with provisionally knowing a few things and having a process for knowing more in the future, and see where that leads us.

And, as we will see in this book, we can accomplish our goal with just that much.

With that lengthy introduction, let us finally get down to the business of looking at the model of Ultimate Reality as per the MSE Framework.

The MSE Framework - Model of Ultimate Reality

We will start at the top of the diagram with the box that has a totally black background, labeled The Great Unknown.

In most religious or philosophical models of ultimate reality, The Great Unknown would be called God or Creator. Some religions think about the Great Unknown in a different manner, such as the concept of Brahman in Hinduism or Tao in Taoism.

We also have some very interesting modern hypotheses for The Great Unknown, such as the Simulation Hypothesis, The Computational Universe Hypothesis and the Wolfram Physics Hypothesis.

I have found many of these ideas fascinating and educational. As a result, I have included Deep Dives into some of these concepts at the end of this chapter. You may find them interesting, too.

But none of these models can provide any proof of their existence. So, we will continue to use the name The Great Unknown because we really don’t know anything about it. Our methodology would not allow us to complicate our model with assumptions and opinions about the nature or features or intentions of this Great Unknown.

All we can say is that we have no choice but to start with something like The Great Unknown, which we will take to be self-evident and fundamental, but beyond that we can’t say anything for sure.

Luckily there is a scientific term for such concepts, “Axioms”.

As a result, for the purposes of the MSE Framework, we will simply take The Great Unknown to be our most fundamental axiom.

Coming back to the diagram, we see two arrows emerging from The Great Unknown. Let us look at each one of them in turn.

Physical Reality

Physical reality, as the name suggests, is the part of ultimate reality that we can either experience physically, using our senses or prove the existence of, using instruments we have created, or using the laws of physics we have discovered.

While we know a lot about physical reality, and can even write formulas that can be shown to work perfectly. At the same time, we still have many unknowns about other parts of physical reality.

We will look at what these unknowns are in the next chapter, but for now, we have indicated this partly clear and partly murky knowledge by using a gradient for the background color of the Physical Reality box.


Just like we can all agree that we live in something like a physical reality, we can also agree that there is something inside us that we call “me”, i.e. Consciousness.

Over the millennia, people have tried to understand what this thing inside of us is, but we are still far from reaching that goal in a scientific manner. But we can say that our lack of knowledge about consciousness isn't as dire as that about Ultimate Reality.

So, the background color of the Consciousness box is gray instead of black or white to indicate this.

We will take a deeper look at Consciousness in a subsequent chapter.

As true scientists, we are simply going to treat both Physical Reality and Consciousness as axioms since they are both self-evident and fundamental to us. Moreover, we treat them both as equally valid and complementary to each other, not in competition with each other like in the aforementioned philosophical debates, again, because we have no evidence pointing to the primacy of either of them.

Let us also note that how Physical Reality and Consciousness emerge from or interact with The Great Unknown is also unknown. Luckily, we do not need to postulate that for our framework due to our methodology which allows us to work with partial knowledge.

Just for completeness, let us note that at the bottom of the diagram, the Consciousness and Physical Reality boxes come together into You. This is the You, as a physical as well as conscious entity, existing here and now and experiencing both.

There is only one little item remaining in the diagram, the dotted line from Physical Reality to Consciousness.

Does Consciousness Emerge from Physical Reality?

What is interesting is that we do not know how Physical Reality and Consciousness interact with each other, but do have clear, widely corroborated evidence that they, in fact, do.

For example, when something happens in physical reality and we perceive it, we can experience it in our consciousness.

Also, our consciousness can direct us to perform actions that affect physical reality. (This is typically known as Free Will, which is another controversial topic that we will not get into since we don’t need to do that for our purposes.)

Physics is the most successful of sciences, and it gives us a great account of all the physical objects and forces that exist. Still, we have not been able to find any force of Physics that can be shown to emerge from consciousness. And likewise, we know of no force that emerges from Physics that appears to act on consciousness.

So how the bidirectional interaction between physical reality and consciousness occurs is unknown.

At present, we have more plausible theories for showing how consciousness may be arising out of physical reality than the other way round. This is indicated in the diagram using a dotted arrow from Physical Reality to Consciousness.

If one of these theories gets proven, we will be able to simply delete the arrow that goes from The Great Unknown to Consciousness and convert the dotted line connecting Physical Reality to Consciousness into a solid one.

This means that, even if that were to happen, the rest of the MSE Framework remains intact. So, we can say that the framework is future-proof to some extent.

Ok, having started with this high-level overview in this chapter, we will be digging deeper into each of these concepts in subsequent chapters, starting with Physical Reality.

Deep Dive: Conscious Realism

Donald Hoffman is an American cognitive psychologist and a professor at UC Irvine.

His theory, known as Conscious Realism, states that evolution did not engineer us to perceive reality as it is. This is because evolution was more concerned with helping us survive and replicate, using as little resources and energy as possible.

Requiring living organisms to know their ultimate reality in order to survive would have required too much energy and resources, because reality is just too complex. So, evolution took shortcuts in our perceptive abilities to let us perceive only the features of reality that offered survival advantage.

Luckily for us, there were enough patterns in our complex ultimate reality that were sufficient for us to survive and replicate without having to know all of it.

But, as a result, what we perceive through our senses isn’t the ultimate reality, but representations of reality, with high correlations with its features that are relevant to our survival.

The analogy is to the user interface of a computer. The UI of a computer does not show us exactly what is going on inside its internal circuits. It only shows us a simplified interface which is sufficient for us to use it. The interface elements are highly correlated with the functions of the computer that we care about, but they look nothing like what actually happens inside.

To put it another way, a map is just a representation of the actual territory, but not the territory itself. In fact, it is impossible to derive the territory accurately from a map.

This means that it is impossible for us to truly understand ultimate reality given that the only access we have to it is based on our perceptive abilities.

Deep Dive: The Simulation Hypothesis

The Simulation Hypothesis as a hypothetical model of what ultimate reality may be like.

But note that it is at best a pedagogical device, not necessarily the truth. Claiming that it is the truth requires taking a leap of faith given that we have no evidence of its validity.

Here is a description of the hypothesis:

Imagine that there is some universe beyond ours in which there is something like a computer on which a game being run. The game involves one or more players that are represented in the game using characters. In gaming parlance, this is known as a Massively Multiplayer Online Role-Playing Game (MMORPG).

The game is so engrossing that the players forget they are in a game and identify themselves completely with their characters inside the game. The only way they can "wake up" from the game is for their game character to die.

You and I are basically individuals who live in this external universe but we are playing this game which looks like our current universe and we identify completely with our characters in the game, which is basically our existence in this universe.

The consciousness that we experience may be the consciousness of this player. This may explain why it remains such an enigma. We will talk more about consciousness in more detail further down.

Many science fiction books and movies have explored this theme to various extents, the Matrix trilogy being probably the most popular among them.

Deep Dive: The Computational Universe Hypothesis

Max Tegmark, a Swedish-American physicist at MIT, proposed that the physical universe is not merely described by mathematics, but it actually is a mathematical / computational structure.

Essentially the idea is to imagine that reality, at its essence, is nothing but a space of all mathematical formulas and algorithms. Somehow, these formulas and algorithms start to expand or execute, which generates all of physical reality, including ourselves in it.

This could be considered to be loosely related to the Simulation Hypothesis , but not exactly the same. It is not saying that there is a reality or players outside the simulation, but the game, as in the Simulation Hypothesis, is all there is.

A major advantage of this theory is that it can answer the hardest question of all: Why anything exists at all. This is because mathematics can be seen to exist all by itself, without anyone having to "create" it. All you need is to accept is that mathematical formulas and algorithms inherently exist in some platonic space.

On the other hand, a big problem with this theory is that it appears to be unfalsifiable and untestable.

Still, it can serve as a great pedagogical device to help us understand various aspects of reality like space, time, quantum fields etc.

Deep Dive: The Wolfram Physics Hypothesis

Stephen Wolfram, a British American computer scientist and founder of Wolfram Research, has a proposal quite similar to that of Max Tegmark's proposal.

He proposes that the universe is a hypergraph consisting of (of the order of) 10 to the power of 500 vertices. There are also rules, known as cellular automata, that specify how to expand this graph based on specified formulas.

The hypergraph started with a single seed vertex and some rule was applied to it over and over until it expanded to our current universe in its current state.

The graph continues to evolve using the rule, and all events in the universe can be thought of as a result of the rule being applied to various parts of the graph, leading to new states of the graph.

Note that, as of now, the actual rule itself still remains to be discovered. But this mechanism can serve as a great pedagogical device to explain how the universe could have evolved and why it has the structure and laws that it does.

Here are some concepts from Physical Reality that could be explained using this proposal.

  • Space: Space at any instant corresponds to a state of this graph at that instant

  • Time: The passage of time corresponds to the evolution of the graph through a sequence of states.

  • Computational Reducibility: Sometimes, a mathematical formula or equation allows you to “jump ahead” and predict the final result of a sequence of steps in the graph without actually going through the process of applying the rule step by step. This is known as Computational Reducibility and whenever this is possible, we end up with a concise formula or model to explain some aspect of reality.

  • Computational Irreducibility: At other times, this may not be possible, depending upon the state of the graph. This means that the answer to certain questions can only be determined by performing or simulating the actual steps. There is no shortcut formula or model to directly jump to the final answer.

According to Wolfram, while most of the hypergraph suffers from computational irreducibility, it contains parts that are reducible. This is what allows us to discover patterns and laws of Physics that work, while at the same time, we have to contend with nebulosity or inability to create concise explanations.

The way we have made progress in physics so far is by following these “veins” of computational reducibility in the hypergraph. But given irreducibility in other parts of the graph, it looks like we will not be able to do this with all of Physics.

As you can see, this theory is a very rich vein of its own, capable of helping us understand many aspects of reality. But it is important to keep in mind that it is only a theory at the moment.

Deep Dive: The Vedic Universe Hypothesis

Vedic Philosophy states that there is just one universal unified consciousness that is the true ultimate reality. It is known as Brahman. Our physical reality, on the other hand, is only an illusion, known as Maya.

According to this philosophy, there is no duality between the self and the ultimate reality of Brahman.

It believes that the ultimate purpose of life is to attain this realization (known as Moksha or enlightenment). It also says that Enlightenment is a process, not a specific destination. One can keep progressing on this path forever. This endows life and consciousness with a long-term purpose.

One of the major benefits of this philosophy is that universal compassion follows as a logical outcome of believing that we are all a part of the same unified reality.

The Simulation Hypothesis can serve as a pedagogical device to understand the idea of Brahman. The external universe that contains the computer where the game is being played, including the player, can together be called Brahman. What we consider to be our physical reality is really just the environment inside the game, and all of us are basically game characters in this game. The consciousness that we experience is really the consciousness of the external player who is playing the game.

This also suggests an explanation for why we are unable to explain how Brahman, physical reality and consciousness all interact with each other, because the entire game computer and its software are outside the game and inaccessible to us.

Of course, this again is only a hypothesis and we don't have a good way to prove it one way or other.

Still, it is interesting that over such long amounts of time and from such completely different backgrounds, people have come up with very similar ideas for explaining our reality. That lends some credence to the idea that there may be a kernel of truth to at least some aspects of it.

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