Our bodies provides a wide variety of sensory input as we interact with the world, and the brain uses this to create a working model, or ‘construct’ of the world. Take the phenomenon of color, for example. Objects that we encounter have various physical properties, including the wavelengths of light which they reflect or absorb. Similarly, our eyes and visual system have their own set of physical properties, which are able to detect and respond to a limited portion of these wavelengths. Our experience of ‘color’ is a phenomenon produced by our brain as a result of this interaction between the physical properties of our environment and our brain. But ‘color’ does not have its own separate physical existence, out there in the “real” world; it is a phenomenon generated within the brain which provides useful information about the environment.
In this fashion, our brains takes the wide variety of sensory data it receives as we interact with the world, and constructs a mental image of the world, which we then perceive as “reality,” often not realizing how this model is created. In some respects, this is analogous to the ‘Virtual Reality’ generated by computers.
(Some modern ‘New Age‘ philosophies go even further than this, and say that we construct reality itself, and somehow draw the conclusion that the physical world is therefore “dependent” on us for its existence. There seems to be no basis for this rather rash position, and it seems, at least from the bottom-line, practical basis I use, that it is closer to the truth to recognize that the world exists in its own right, independent of having a human around to perceive it.)
So then, as we live and interact with the world, our brain constructs a working model of our environment, to help us successfully live and reproduce (the natural result of the evolutionary process underlying the development of life). But as incredible and useful as these mental constructs are, they can be readily fooled. Optical Illusions serve as excellent examples, which can be easily experienced by most people with intact visual systems. For my purposes here, it is helpful to distinguish between two types of illusions:
This is a fairly famous illusion, where one can either see an old woman with a large nose facing to the left toward you, or a more beautiful woman facing to the left away from you. You can see one or the other, and effortlessly switch back and forth between them. But which of these is “real” or “true”? The drawing itself is real and objective, but the pattern-seeking processes of our visual systems interpret this single reality ambiguously, in differing and mutually exclusive ways.
I have used this next illusion before, but find it quite compelling:
When we look at the Squares labeled A and B, we can see that obviously Square A is considerably darker than Square B. But it turns out that they are in fact the same exact shade. Because of the specific ways that our visual systems have evolved to interpret the light coming in through our eyes, and which will be accurate in most instances, there are situations where they will be fooled.
I had to prove this to myself by opening up the image in Photoshop. And yet despite having proven to myself that these square are the same shade, I am unable to convince my brain to actually see this “reality.” So this is an excellent example of where we will draw factually incorrect conclusions about the nature of reality based on our subjective experiences, and where “seeing is not believing.”
In a similar way, people of a religious mind-set typically rely on their subjective experiences, and on this basis, they draw conclusions about the world, how it came to be, how and why things happen in it, etc. What they fail to take into consideration, however, is that this particular kind of subjective experience is no more reliable than our sensory perceptions, in establishing what is true. In fact, it is likely much less reliable than ordinary sense perception, in that it depends more on the complex processing and interpretation taking place within the brain, and considerably less on direct physical sensory input.
Religious “testimonies,” which proclaim absolute truths about the world, however well-intentioned, however profound and self-evident they seem to the individual, are simply unreliable. This is the inevitable conclusion to be drawn when you begin to understand the basis for how the brain works, and how we generate working models of our environment. And this is further confirmed as one studies human religious experience throughout history, and sees the widely divergent, and typically mutually exclusive, conclusions that individuals draw about the world on the basis of their religious experiences.
So if we can’t implicitly rely on our own experiences, nor the information provided directly by our own senses, to differentiate between truth and error, how do we then make these critical distinctions?
This where Science comes into the picture. The value of the Scientific Method, and its accompanying logic, is that it enables us to transcend the limitations and subjectivity of our senses, of the idiosyncrasies of the information processing that takes place in our brains, to provide hard data, which can be independently tested and verified by multiple observers. It also provides a means of systematically uncovering and eliminating various forms of bias, and results in drawing conclusions solely on the basis of what the evidence will support.
It should be acknowledged that science does not produce “absolute” truth, and by definition, deals only in probabilities. But the crucial point here is that it provides a mechanism to progressively get closer to truth, and further from error. It is self-correcting by its very nature, and non-dogmatic (even though individual scientists themselves can be quite dogmatic at times), which is quite different from the absolute pronouncements of many religious individuals and institutions, where ‘revelation’ is alleged to demonstrate truths which cannot be challenged or changed.
At this point in my life, I see the use of the Scientific Method as the only legitimate way that we currently have available that will enable us to differentiate between truth and falsehood, and this is therefore the basis upon which I will live my life. I remain open-minded on basically any and all questions, including the “ultimate” ones, but require that any claim be backed up by evidence obtained using the rigorous methodology of genuine scientific inquiry.