I like to divide knowledge into two distinct categories. The problem is that these categories can overlap, and the shifting gray area between them is where ideas of truth, proof, and logic become difficult to handle.
My first category is concrete knowledge. This is objective fact, things that can be empirically proven, at least as far as anything can possibly be proven. An example from this category would be the statement “the earth is round.” In order to determine that the earth is round, you can perform tests to gain results from external sources of data.
The second category is what I would call logical knowledge, ideas that are founded on subjective reasoning rather than external data. If someone says “there is a god”, they are making a statement based heavily on reasoning within their own mind, since you can’t go stick scientific instruments in a supernatural being and produce data that shows its existence. They may base the idea on external data, such as the bible, but they can’t measure God. There are no tests you can perform to validate the claim.
The gray area, then, is where we find concrete knowledge challenged by our own reasoning, or vice versa. A few religious fanatics still exist who maintain that the earth is flat, based on passages from their bible, despite all the evidence that it is round. They choose their own reasoning—how they interpret the bible—over concrete evidence.
The ways these two facets of knowledge interact are complex. In order to gain logical knowledge, often we take several pieces of concrete knowledge and put them together with reasoning. This very article is logical knowledge; I have no way to collect external data on types of knowledge, and I’m working with the assumption that other people’s minds are similar to mine, based on my concrete knowledge of the brain and external data collected during conversation with others. As a result, you could start with different data, approach the issue in a different way, and argue against my ideas by proposing a different list of three or six or twenty types of knowledge.
However, even if you were right in doing so, that wouldn’t mean I’m wrong. People can be neatly divided into two distinct groups based on whether or not they have a Y chromosome, so if you were writing specifically about something that concerns people with Y chromosomes, such a division may be useful. The fact that people can be divided into several more different groups based on gender, biological sex, and chromosomal disorders is irrelevant in that case.
I can divide knowledge into just two categories because I’m concerned with the method used for gaining it, and there are two fundamental ways—knowledge from outside you, and knowledge from inside you. Of course, this doesn’t cleanly divide information into one category or another. Concrete knowledge, at some point, starts out as logical knowledge. People may have reasoned that microscopic organisms existed before they had the tools needed to verify the hypothesis. The fact that bacteria exist has always been objective truth, but knowledge is distinct from truth and facts because it’s defined by what you think, not what really is.
This brings us to a possibly startling conclusion, that a fact may be concrete knowledge to one person, and logical knowledge to another. Suppose that God is real. As I said before, in order to know he is real, you must rely on your own reasoning. But then, suppose that you meet this God face to face, and you receive empirical data that convinces you of the reality of the encounter. Some people would think you’re crazy, while others agree with you because they have logical knowledge of God. Logical knowledge is mainly defined by the presence of unknowable variables, and we have another word for it: faith. Simply put, faith is belief that is not based on proof.
Here’s where the matter of knowledge gets really weird. Can you empirically prove, using objective data, that everything you experience is in fact real, and you’re not a crazy person in an asylum somewhere? You can ask other people, and they might tell you that it’s all real, but they could be figments of your imagination.
The unknowable variable here is your own mind. Every single thing that you think you know is based on the reasoned assumption that your perception is correct. With no possible way to objectively verify whether or not your view of anything is accurate, we come to another startling conclusion: concrete knowledge is impossible, and nothing can be empirically proven.
But that is true only if you’re looking at it from a totally objective viewpoint. As I said, knowledge is defined by what you think, not what really is. When talking about knowledge we can ignore the possibility that we’re all hallucinating brains floating about in a mad deity’s laboratory, and focus on what we are experiencing. Whether or not the world you see actually exists, it is real to you, and that is what matters.
Returning to the gray area between concrete and logical knowledge, then, it’s easy to see what causes all the confusion and disagreement we have over what is true. People have different data to start with, the way you approach a subject can change how you see it, and our perception, even if we set aside the possibility of being insane, is still unreliable. We sometimes argue about concrete knowledge (the earth is round) because the other guy is standing on his own reasoning (the earth is flat). Or perhaps we all have concrete knowledge that conflicts due to faulty sources. Or we may argue about a subject that is subjective for everyone involved (the existence of a god).
All of this argument, every fight over what is true, comes down to an innate need for stability. The idea of being wrong feels threatening because our entire lives are founded on the unprovable assumption that what we perceive is actually real. I think that when you have knowledge, either concrete or logical, and you face evidence that your knowledge is false, it shows you a glimpse of your flawed perception, and it scares you for the same reason most people fear death. It’s the unknown that gets to us; we fear our inability to know for sure.
This is why it’s so important to respect the beliefs of other people, and validate their ideas and experiences. You can’t prove that your perception is more correct than theirs. All you can do is share what you know, and listen to what they know. Maybe one of you is wrong, maybe both, maybe neither. But for both of you, what you know is your reality, and alongside our need for stability is a desire for shared reality, for people to know what we know and empathize with us.
An argument is both a fight against the fear of flawed perception, and a search for reassurance of correct perception. Many people I’ve debated have insisted that they know the absolute truth. Aside from being impossible, such a claim is unproductive and only inflicts more fear on your opponent. Don’t approach disagreements with a stubborn assumption that you’re right and they’re wrong. Approach disagreements with your mind open to the infinite unknowable possibilities.