Class Warfare Blog

October 18, 2019

The “Limits” of Our Understanding

Filed under: Philosophy,Reason,Religion,Science — Steve Ruis @ 1:30 pm
Tags: , ,

I am reading a book whose subtitle is “The Limits of Science and the Search for Meaning.”

I just got started so I don’t have much to say about the book, yet, but I did have a reaction to the use of words. In the introduction the author, after much dissembling, talked about how every measurement is inexact, that they only go so far. But then the word used became “limited” as what we do know and can measure is “limited” and inferring that what we can know is limited. And then, of course, the author wonders what those limitations are. But phrases are then used like “The ultimate truth is elusive, a phantom.”

I am girding my intellectual loins to read this book, so we will see how I evaluate it when I stop (finished or not). There seems to be more than a little bit of Platonism in the language used so far. The idea of an ultimate truth, in itself, is disturbing to say the least as this idea has only been used by charlatans claiming to know a “truth” that we do not possess and then trying to extract something from us in order to share that “truth.”

Let’s talk about the limitations of measurements to begin with. I used to stand in front of a lab class and ask them how long the lab bench was. People guessed that it was maybe 20 feet long. I responded that that was a good start. I pointed out that the floor had vinyl tiles on it, each of which was 12 inches/1 foot in length and with a little counting we came up with a better measurement. Then I provided a meter stick (Hey, we’re talkin’ science here! You were expecting a yard stick? Go to the hardware store!) And they were able to get an even better measurement from multiple uses of that instrument. Then I pull out a steel measuring tape, and voila an even better measurement!

Finally, I suggested we could walk over to the physics department and borrow a laser interferometer which could measure lengths to a fraction of a wavelength of light! And I asked them what we would find. They all assumed “an even better measurement.” And I said, “Uh uhn. What we would find is that the far edge of this bench is not parallel to the near edge and that we would get different measurements depending where we took the measurement. And even if the two edges were perfectly parallel, we would find that at the realm of wavelengths of light, that the edges were neither perfectly smooth nor perfectly flat and we would start having problems deciding where the bench began and where it ended.

Measurements are necessarily inexact, but it is rare that this is due to our inability to measure accurately. It is usually due to misconceptions, for example that the bench in my teaching lab had a “true length.” The same thing goes for things like atoms. Atoms have no exterior surface, so how do you measure their sizes (from . . . , to . . .)? Even the idea of a perfect object, a Platonic “ideal,” is completely unreal. It is an idea we can have but we cannot create. And can we know the ultimate truth? about anything? Well, basically, my response is “You want the ultimate truth? You can’t handle the ultimate truth!”

This book’s topic impinges on recent posts of mine regarding the nature of reality and how our senses and brains create it for us. We are curious by nature—hardwired in, it is. So, we take things to extremes in our imaginations (because “Enquiring minds want to know!”), but if we start thinking those extremes are real, then our only future is one containing a great many rubber rooms.

Let me give you a ‘for instance’ from the history of science. It was Isaac Newton, in our western tradition, who “discovered” that the force of gravity showed fidelity to an inverse square law, that is the force was inversely proportional to the square of the distance of separation of the attractive bodies. In math, for two gravitationally attracted bodies, say you and the Earth, it looks like this F = k m1m2/d2. The distance, d, is between the two centers of masses of the two objects and the little m’s represent the masses of the two bodies. The proportionality constant, k, makes the units of measurements agree with one another. So, this was in the 1600’s. How well do you think that Newton’s estimate of an exponent of exactly 2 was measured? Could it not have been 2.01 or 1.98 or 2.00002 or 1.9999997? Well, it could be, but this is not how science works. Scientists find that in many, many things, simple integral exponents like 1, 2, or 3 show up quite often, so if the data indicate it is very close to “2” we assume it is “2” for the time being. This has been checked and the exponent is 2 to about eight decimal places . . . so far. As long as Newton’s law of gravity gave us good answers to our questions we used it. When it stopped giving good answers, then we look further into the rule to see if there are limitations to its application. (Einstein’s theory of gravity got props for explaining things that Newton’s theory could not. This does not mean that we stopped using Newton’s theory, we just became aware that there are preconditions for its successful use.) In this fashion we do not need perfect information to proceed. We proceed from the imperfect to better.

Could we ever determine that the exponent in Newton’s equation is “exactly 2?” I suggest that we cannot as we either end up having to expend so much effort to get the next few decimal points, only to end up with there being more to check, or we find out, like the length of the lab bench, that our question becomes incoherent.

So, are there “limits” on how well we can understand things. Absolutely, but these are not philosophical limits or necessary physical limits. And these limits are not necessarily from without (except, consider Heisenberg’s indeterminacy principle) they often as not come from our misperceptions of the actual situation we are in. You name the problem and I can give you a long list of potential limitations to us acquiring an answer. For example, consider the question: What is “dark matter?”

Here are some potential limitations on our being able to answer this question:
• The experiments needed are very expensive and no organization will fund them.
• Global climate change creates an existential crisis and we end up spending all of our energy on practical questions.
• Aliens visit us and destroy the planet.
• We develop an AI that metastasizes, takes over the planet, and exterminates human beings.
• Through genetic manipulation, we create a super plague that wipes out humanity.
• We discover that the universe is different from what we thought is was and neither dark matter nor dark energy are needed to explain anything (this is the same as “nothing to explain” and trying to explain things that do not exist, well that is better let to theists).
• An alien invasion involves us being genetically manipulated by viruses, lowering our IQs dramatically because they want us as meat animals.

Speculating as to whether our ability to understand science is “limited” is possibly entertaining (sells books, even) but is likely to be as wrong as all other speculations about the future. Plus, if our ability to understand “the natural” is limited, consider then what limitations might be on our ability to understand the supernatural. (Yes, I believe there is a religious context behind such discussions of the “limits” of science.) The only way to find any such limits to applicability of any science is to attempt them, over an over; it is by doing, not thinking that such things are found.

I am reminded of my ex-wife who was a biochemist and who had gotten a job at a plastics firm. She was assigned to a workgroup and the leader of that group told her they had been working on a problem for the better part of a year and gotten nowhere and wondered if she had any insights. They were trying to come up with a solvent for a new plastic. She said she would think about it. She went into her lab and took samples of the plastic and then took down bottles of every solvent there and added some of the plastic and some of the solvents in small glass vessels. Within a couple of days she had found three decent solvents to continue testing. Her supervisor was looking for a solvent which could theoretically meet their needs. She was looking for a solvent that could actually meet their needs.

This, by the way, highlights the differences between philosophy and science. The scientists have nature to settle disputes, philosophers only have each other.

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