A plea to common sense is a common tactic used to justify that a claim is true. Today I am going to challenge that notion. Commons sense as an argument is a terrible argument in a lot of situations. You might be inclined to think, “What does this have to do with autism?” I’ll argue that being autistic has put me in a position to challenge the notion of common sense because of the social implication of the concept.
Merriam-Webster defines Common sense as: sound and prudent judgement based on a simple perception of the situation or facts. The definition seems simple and, on the surface, there isn’t much to argue, but there is a lot to understand beneath the surface.
The first thing to look at is the “simple perception” part of the definition. I have an associate degree in physics. One thing I learned while studying physics is that our initial perception of things can’t be trusted as much as we would like. An example would be the idea that the Earth is the center of the solar system. At one time this idea would have been considered common sense based on the available facts. One day Copernicus challenged the common sense of the time based on new evidence and new facts. Sometimes our simple perception is based on incomplete information.
The second part to look at is “facts.” Another thing that you learn while studying science is that facts are tough to nail down. That is why science uses the idea of “reasonable certainty.” We must understand that there is almost always some level of uncertainty in anything we think is true. In all cases scientists must deal with uncertainty in measurement because of the limitations in precision of measuring instruments. There comes a point with a measuring instrument where we can’t be certain that the measurement is what we think it is. Think of it this way: take a ruler or tape measure, then try to divide between the lines at the half way point. Keep dividing between those lines until you can’t be certain that you are dividing at the half way point. Eventually you will get to a point that you can’t be certain anymore, and any measurement after that point is uncertain.
When it comes to facts we also must consider what we don’t know. No one know everything, and this is important to understand. When we develop an understanding about something, we do so based on the data that we have at the time, but that can be incomplete and can skew our understand of the truth. Reasonable certainty considers the fact that we might not have all the data. In physical science, a “theory, is a hypothesis that has gone through all of scientific method and considered to be reasonably true based on the available data. It’s understood that new information, that we weren’t aware of, may come to light and disprove the theory in whole or in part. Because of this, a person making a plea to common sense may very well have incomplete information and be forming a conclusion that is inaccurate or false.
A plea to common sense also gets used in a way that the definition doesn’t reflect. On many occasions common sense means: A commonly held idea by a group of people that is considered true. Depending on how, and when, it’s used it can be an informal logical fallacy known as an “argumentum ad populum.”
Just because a group of people believe something to be true, doesn’t mean it is true. A group of people can share a belief that something is true that isn’t. As an autistic person, this has caused me a lot of problems socially. I have taken stances on topics that I am more educated on than the person/people I am debating with.
Politics is one of my special interests, and I am a PoliSci major in my senior of college, and I run into this a lot. Common sense seems to tell a lot of people that poor people are the reason they struggle financially. The idea is that the government taxes them and then gives their money to poor people. The reality is, the average American that pays into taxes doesn’t really pay much of their income into safety net programs for the poor. The last number I saw on this said that the average American who pays into taxes will pay $42 a year to safety net programs for the poor. Most of the money that comes out for safety net programs comes out for things like social security, unemployment, and welfare for large corporations.
I’ve worked and paid bills throughout my life, and I can say with a high degree of certainty that when I follow my money, most of it goes to business people. It goes to people who make a lot more money than I do. My money goes to the type of people who set the wage of employees and set the prices for goods and services. The facts show that the reason I don’t have a lot of money is because my wage barely covers my expenses, the two things in the control of people who have more money than me. On top of that, my taxes go more to support large corporations than it does the poor.
Using this information, I could develop a hypothesis. My hypothesis is, given the data I have, that I would find that poor people don’t have a lot of money, even if they are using a safety net program, and that rich people would have a lot of money. Low and behold, it’s true. Someone making the argument that it’s common sense that they are struggling financially because poor people use safety net programs seems to be false. This is an argument I have heard many times, where people used a plea to common sense as grounds for how factual their claim is.
Often, notions like the one above occurs because a belief takes root in a social group and there is a drive by non-autistics to align their beliefs with their social group. In many cases they are unwilling to change that belief in the face of evidence and logic to contrary because they fear being rejected by their social group.
Being autistic, this isn’t something I worry about too much unless it has significant material consequences. As a result, I have found myself challenging “common sense” a lot during my life. Common sense is one of those terms that seems to hold a lot of weight with people but is tremendously problematic. A plea to common sense doesn’t automatically make a person’s claim correct and that’s important to understand. It doesn’t mean that it’s useless. Common sense should tell most people not to jump off a skyscraper, and for good reason. This is one of those things that life experience should teach us, and that science can back up with a very high degree of reasonable certainty. If you have ever struggled with the idea of common sense, please leave a comment and talk about it.