We use our ability to reason for a great deal of things, and I think the answer to this sort of question lies mostly within the definitions used. What is reason, and for that matter, ultimately, what is truth? Can we reasonably determine the cause of the universe? Or even ourselves? Let’s take a look at some of these questions and see how things shake out.
What Is Reason?
The power of comprehending, inferring, or thinking especially in orderly rational waysDefinition of Reason – Merriam-Webster
Reason is our ability to give meaning to world around us. It is how we interpret our observations and create “cause and effect” correlations. There is no question that humanity’s most meaningful attribute is our ability to reason. It has allowed us to overcome great obstacles and to create civilizations allowing our populations to flourish. It has also led to incredibly misplaced notions and catastrophic wars. But can reason lead us to truth?
What Is Truth?
The body of real things, events, and factsDefinition of Truth – Merriam-Webster
Well this complicates matters a bit more. You see, truth isn’t simply based on that which we observe. Our observations are subjective and consistently altered by our own brain. Truth, rather, is the body of real things, events, and facts as they actually occur, not simply what we observe to be true. Let me give you an example.
Can We Trust Our Observations?
Examine the image below. You can see that the pink dots are disappearing one at a time in a clockwise fashion. However, if you stare at the plus symbol in the center of the image, you may see a green dot appearing to move around the circle. Is there actually a green dot or isn’t there?
This is an effect of neural fatigue. Your mind begins to fill in the gaps for you because, based on the image a moment ago, something should be there. As the dots disappear your mind fills in the gap with what it thinks should be there. At least, that’s what we think happens based on what we observe, which we have just proven to be unreliable at best. So, take that for what its worth.
Can We Determine Truth If We Cannot Trust Our Observations?
Well, not really. How could we? Everything we experience is an observation of a past event. By the time our brain is aware of what is happening, light has traveled from the event, to our eyes, and transmitted to our brain. Any event that we were observing has already happened. In this way, our brain is the sole source of our experience. How do we know that we can actually see, smell, hear, or feel? If each of these senses are information that has been sent to our brain and is interpreted there, how do we know that the information was actually sent at all? In other words, how do we know that we are not just a brain in a jar dreaming our reality?
Cogito Ergo Sum (I think, therefore I am)René Descartes
This philosophical proposition was made famous by René Descartes, a 17th century French philosopher. The idea is that all we know is that we can think. We cannot prove logically that we even exist outside of our minds. Our reality could quite reasonably be conjured by demons merely to torment us. Or a more modern example, a computer simulation that we are experiencing while sedated, think The Matrix. If we cannot prove that anything outside of our consciousness exists, how can we expect to find truth?
Let’s Assume We Exist As We Observe
So let’s just assume that we do exist in a shared reality, just as we though we did a few moments ago. Can’t we use reason to determine, in our observable reality, that which is true? In some cases, this may be possible but I think that another example might display just how shaky our concept of truth really is.
How much do you weigh? No really, go ahead. I won’t tell anyone, I promise.
From time to time, maybe even daily, you step on a scale to see how much you weigh and you’re either content or disappointed about the result. Either way, you leave the situation knowing ho much you weigh, but do you really know? What causes your body to have weight? That’s easy, gravity right? We know how much we weigh because we have created a system that takes a constant unit (lbs or kg) and tells you how many of those units are equal to your weight. This system ultimately relies on the idea that gravitational force is constant. Now, although the is a value out there that is used as a mathematical constant for the sake of performing calculations, there is quite a bit of debate about this number. It seems that determining what the true force of gravity is has been a rather difficult task.
In 2011 and in 2013 a group of researchers in France calculated the gravitational constant using the same equipment and process each time. Guess what? Their results were different! Had the gravitational constant changed or is the method of calculation unreliable? Perhaps we could determine the answer to that question if we knew how gravity works… Oh yeah, we don’t really know how gravity works. We know that we can estimate the strength of gravity and use it for mathematical equations and, on a small scale, get an answer close enough that it works for, let’s just say, space travel or telling you that you need to lose weight. Beyond that though, things aren’t very steady.
So, one more time, are you sure that was your actual weight? If we don’t know how gravity works, and we don’t know if it is a steady force, how do we know that you actually gained a pound yesterday? Of course, we can reasonably assume that gravity is steady and constant, but we aren’t asking if we can reasonably assume something is true, we want to know if it actually is true. Do you think that is possible?
If it is this difficult to determine truth regarding things we can observe, how can we hope to use reason to determine truth regarding the things which we cannot observer, like the origin of the universe or the nature of God?