Now obviously one blog post will be insufficient for answering this question. But that’s fine. Perhaps “what is real?” is an unreal and irrelevant question. Or perhaps it is the most meaningful question ever to have been asked. How could anyone know?
Levels of Reality
I shall take as a starting point the film Inception. In it, the dream-within-a-dream motif cascades down several times, creating many levels of reality within a coherent story. In each successive level, the dream world is more fantastic, with what would otherwise be logically impossible objects, until the final stage called Limbo, in which entire worlds can be constructed, built convincingly enough to fool a dreamer’s belief in reality. But this raises the question of which stage should be called reality. If a dreamer has been in Limbo for decades, maybe centuries, he would have spent more time in a dream than in the original level of reality, and thus Limbo would seem more real to him than the original reality. In fact, he may even forget that the original reality ever existed. Limbo would not just be a more relevant reality—it would be the only reality.
This assumes that Limbo is convincing enough. For Limbo to work, it must fool our senses so much as to cover truth with a blank canvas and let our imagination paint it with only the facts we choose to accept. Then we choose to accept nothing else, so that we have quite literally our own picture of reality.
Now Limbo is purely a fictional concept. But perhaps you have already taken Limbo as real in some part of your imagination. Maybe you have already begun to formulate your own realities in Limbo. Maybe you are designing the architecture as we speak. If so, you should pat yourself on the back for doing your job as an open-minded reader.
If, on the other hand, Limbo seems to you just as false as unicorns and the tooth fairy, then perhaps the canvas has already been placed in front of your eyes. Your own opinion of reality has excluded the possibility of Limbo, because you find it outside of what you want to accept. Since you do not think it is true, it must be false. Thus you may already be inside your own Limbo.
The trouble is, it is somewhat difficult to tell whether we are in a false reality. Maybe we are merely trivial details of someone else’s dream. We might be in Limbo and thus not be real.
“I am real!” you might say. In the Limbo-sense of real, then yes, everything is real. Anything we can imagine is real within someone’s imagination. Going down one level is easy. But going up is the hard part. What kind of experiment would be able to tell us whether we are in a true or false reality?
Perhaps there is a giveaway error. In a dream, if you flip a light switch, the light might not change. But we can only detect this error because we are expecting the light switch to do something. If we only remembered what happened since the start of the dream and remembered nothing of what a light switch was supposed to do, then we would not be able to conclude anything when we flip it. The room would stay dark, but that would not say anything about being in a dream or not.
So maybe there is some analogous error that we can find with our common reality. But if the case is like the above, then we have no idea what we are searching for. In fact, we may have already stumbled upon the giveaway error that proves we are in a dream right now, but we do not know how to interpret it. Perhaps when you place oxygen molecules near one another, they are supposed to trigger a nuclear explosion. But in our level of reality, they do not do anything—we just breathe them in.
If we knew that flipping the light switch should trigger the light, but it doesn’t, we would deduce that we are in a dream. And if we knew that oxygen molecules should cause nuclear explosions, but they don’t, then we would likewise deduce that we are in a dream. But how are we supposed to know that oxygen molecules should explode? It would be knowledge coming from outside our universe, and would be hence unobtainable unless there were intervention from outside. This could happen if some entity came down to us, demonstrated supernatural powers (e.g., causing many black holes to form in the sky, without destroying Earth), and told us that we are in a dream. Most people would consider this entity to be a god.
But there are still issues with this method. What if the entity was not a transcendental being, but rather, just an alien with advanced knowledge of physics playing a prank on us? If that were the case, would most civilizations in the world still think of this entity as a god?
Questions that Cannot Be Answered
The common belief is that if a question has no answer, then it is not meaningful. I claim that this is false, by showing examples of questions that cannot be answered and yet are meaningful. Historians, for instance, would benefit a great deal from investigating the many mysteries of mankind. But this is a cheap example, you might say. A question such as “Who shot John F. Kennedy?” has an answer, and perhaps some people alive today even know it. But surely no one today knows the answer to the question “When did Homer live?” or even “Was Homer a real person?” Even so, these questions do have answers; we just can’t find them.
There are some more bizarre questions, however, in mathematics. For example, “Can every even integer greater than or equal to 4 be written as the sum of two primes?” The answer must be either “yes” or “no,” but no one has found a proof yet. Much worse are Gödel’s incompleteness theorems, which imply that there are true statements that cannot be proved. Equally bizarre is the question “Is there a cardinality between that of the natural numbers and that of the real numbers?” The answer is, almost paradoxically, that both “yes” and “no” are valid answers, which seems to raise the question of whether this constitutes an answer at all.
Then we go on to physics and metaphysics. “What is time?” “How did the universe begin?” “Is our universe a false reality?” I think that all of the questions in the last few paragraphs are relevant for us. Knowing more about time could, in the far future, open up many new technologies and possibly time travel. Knowing how the universe began would tell us much about the laws of physics, which we still don’t quite understand. And knowing the reality of the universe would grant us some much-needed insights about the truth, of which we are ever in pursuit.