A Digression about Intuition, Models, and Reality

Recently, I have had some interesting discussions about models such as physics and math. Writing my last post about the "human and life model" has helped me develop my thoughts further. I feel that writing about these thoughts is appropriate now as we have just explored a very simple model of the human, and I wanted to write these thoughts down while they are fresh in my mind.

I view the world in a very strange way compared to many people. I also find it extremely difficult to express this view because it involves very subtle concepts that can easily be misinterpreted. I will try my best to describe my view on models and how we perceive the world, although it is likely it will take some thought to truly appreciate the full extent of what this represents.

Human intuition is very narrow. It will be completely wrong in most cases, but for the tiny portion of life that we see everyday, it is extremely accurate and efficient. Since we grew up seeing a portion of the world, our brains have wired themselves to deal with the part of the world we see. For example, it is intuitive that when we drop something, it will fall "down." It is intuitive that the blue colour we see in the sky is normal. It is intuitive that people cannot walk through walls. In this way, our brains build a simplified model of the world. And in the size, velocity, and time scale that we see everyday life in, most things just seem to make sense. But intuition is learnt, either though life experience or though the lengthy process of evolution. But as we see, intuition is completely wrong when it comes to things that we rarely encounter, and this includes the part of the world that we do not see.

I will now describe some famous cases where intuition breaks down, so if you have not heard about these experiments before, I highly recommend you read about them. On a size scale much smaller than our everyday world, quantum mechanics indicates that matter decomposes into both particles and waves, with some very strange results. For example, the double-slit experiment done with a single photon at a time concludes that a single photon will travel through one of the two slits if we try to observe which slit the photon travels through. This indicates that a photon is a single particle. However, if we do not try to observe which slit the photon passes through, an interference pattern on a screen opposite the partition clearly, without doubt, shows that the single photon had travelled through both slits at the same time! Not only that, but the photon, which we have just observed as a single particle in the last experiment, is now also clearly shown to be a wave that spread out through space! How can this be possible? Our intuition tells us that this is an impossible result, even though the experiment can be easily replicated on a tabletop set-up.

Similarly, at time scales much shorter than what we encounter in everyday lives, we see that energy becomes ill-defined due to the Heisenberg uncertainty principle. And since energy is the same as matter, another unintuitive concept, this means that particles and antiparticles are constantly popping in and out of existence out of nowhere! But this model explain many previously unexplainable observations, such as the Hawking radiation from black holes.

Another easy example is at velocity scales that we do not see in everyday life. At velocities close to the speed of light, once again, we need to us a very unintuitive model: Relativity. Our intuition would have resulted in completely wrong conclusions working in these conditions.

So we see that our intuition can only be applied for a very narrow range of situations. This is troubling, because this means that we have a very deluded view of the world. Most people do not realize this. They hear about all of these strange results, such as from quantum physics, and think "oh, that's strange. It's cool there are so many strange things in the world that do not make sense." What most people do not question is that perhaps our view of the world is completely wrong, and that nothing is as what it seems. Perhaps we are thinking about the question in the wrong way. Instead of trying to make the observations fit in with our intuition, we really should be working to mold our intuition to fit the observations. Yes, change is scary, but necessary in a learning process.

In a way, our intuition is our simplified model of the world around us, much like the simplified model of life I presented in my previous post. It is very useful and effective at what it is designed for, but reveals nothing about the true nature of things. This also goes for other scientific models such as physics, math, and chemistry. What do I mean by these models reveal nothing about the true nature of things? This is the concept that is difficult to explain and easy to misinterpret, but is the essence of the way I view the world, so try your best to understand it.

Probably the easiest to understand the best known example of this is explored in the movie The Matrix. How do we know that we are actually here? What if our brains are just stimulated in a manner that allows us the think that we are here? What if we are just a complicated experiment being performed by some kind of outside beings living in an environment with completely different physics? How do we know we are not just playing a very advanced video game of some sort where you can choose your life and your world, and by having the computer interact with your brain, you can play out an entire lifetime during your lunch break? You see, this idea gets to the fundamental question of what reality really is, rather than what we intuit, or model as. Of course, many of your science-types will bring up Occam's Razor at this point. But let me point out that firstly, Occam's Razor isn't always necessarily correct - don't get me wrong, I am a firm believer in Occam's Razor, but I always think before applying it. Secondly, Occam's Razor is based on intuition, and yes, it describes our everyday world very well, but fails at things we are not familiar with. For example, I have applied Occam's Razor to physics many times and ended up wrong. True - after working with the theory, I can now use Occam's Razor in physics and be right most of the time, but I had to develop an intuition about physics first. But when dealing with things we do not encounter on a regular basis, we cannot apply Occam's Razor as we do not know which parts of the model are important, and which parts can be dropped.

Another example that I have always pondered about is the universe. Most scientists would agree that the universe if of a finite size. But if the universe is of finite size, what is beyond the universe? Empty space? But if it is empty space, can't we still count that as part of the universe? So again, either our intuition about "empty" is wrong, or our intuition about "size" is wrong. These are extremely basic ideas, but we see they fall apart when applied to parts of the world we do not have intuition about. And here's part two of the "difficult to explain, but easy to misinterpret" idea:

My view is that because the human mind has evolved seeing only this narrow segment of the world, and we have rarely or never experienced anything different, it is impossible to ever fully understand the true nature of the world. Yes, we can create models based our observations and obtain intuition about these models, but the basic ideas that these models are based on are still intuitive ideas. For example, math is intuitive because even the most complicated ideas such as multiple dimensions, complex Riemann sheet branch cuts, Schwartz-Christoffel mappings, Green's functions, and others, are still based on a few basic ideas such as addition, subtraction, area, volume, and other intuitive ideas. Physics models are intuitive because they are based on mathematical descriptions. But the reasons behind many basic assumptions of physics are unintuitive. For example, who really understands wave-particle duality? Yes, the idea is simple because it is based on our intuition of waves and our intuition of particles, but who can really explain why something is a wave and a particle at the same time, and what a wave/particle really looks like? Yes, yes I know, it's just a wave function that collapses to a probability distribution, but this is only the "intuitive" model of a true wave/particle. We see two problems with the way this wave/particle is currently interpreted. The most accepted interpretation is that the wave exists (i.e. the particle is everywhere but with varying probabilities), but only collapses down to a particle upon observation. The catch is, "observation" is never defined in physics, so saying the wave function collapses to a particle upon "observation" is merely saying "we can interpret it either way, whichever is more convenient for us at that moment." This completely lacks any mention of the true nature of this wave/particle. But even though the model does not say anything about the true nature of the wave/particle, it is still extremely useful because it can be used to predict behaviours of the wave/particle, allowing us to manipulate it into something useful.

So we see that effectively, we do not know anything about the true nature of the world. There are even things that we can observe everyday and have no intuition for, such as consciousnesses and where it comes from. And we see, as we do not have an intuition for consciousness, we also do not have a scientific model for consciousness, as science is based on intuition. Perhaps when our view of science changes in the future, we will eventually be able to explain consciousness, but it is possible that consciousness will never be explained adequately by science.

In effect, I am saying that the true reality of the world cannot be understood by intuition. And since intuition is really the only way we can truly understand the world, I am saying that unless something dramatic happens, we will never truly understand the world, because in a way, our understanding is limited by what we experience and the capabilities of our senses and minds. However, I am not saying that we should give up on trying to understand the true nature of the world and just ignore the problem. I am saying that we should keep this fact in mind so that we can continue to try to get closer to understanding the world, and when we see or hear about something we disagree with, we should try to understand why the other person may think that way. Because everyone has their own experiences, they have their own interpretations of the world. We should try to learn from each other and try to understand as many of these interpretations as possible, because only in understanding many interpretations can we start to see patterns and achieve a broader understanding of reality. By working to understand everyone's ideas and intuition, we share experiences and learn from all of society rather than just from your own limited experiences. In effect, by exploring and sharing new ideas, we experience much more of the world than we ever could by ourselves.