People ask questions. For instance, I’ve had students ask me “On what basis, other than the Bible, do you have that God is real and that what you believe is true?”
Is God real?
One can give theistic evidences, of the classic sort as given by Thomas Aquinas, for instance. But, fundamentally, I think the question of God’s existence is a presuppositional issue. That is, like Euclid's axioms (such as the definition of a point, a line, etc.) there are no proofs. One simply assumes them as basic ideas, and then one builds the rest of geometry from them. Likewise, I think the existence of God is an axiom. Everyone has presuppositions.
How do we know that reality is really there? You think you’re sitting in a chair reading this book, but how do you know that you’re not actually a disembodied brain in a laboratory somewhere, soaking in a vat of nutrients? It could be that a mad scientist has attached electrodes to your brain, and he is feeding a stream of electrical impulses that exactly simulate the experience of sitting in a chair, reading a book. How in the world could you ever disprove such a theory?
After all, everything that you experience of the real world is mediated through your senses of smell, taste, touch, hearing and seeing—and yet those senses come to your brain by way of electrical impulses, that your brain is able to translate into a perception of reality.
There is an ancient Chinese tale about someone named Chuang-tzu, who lived sometime in the fourth century BC. It seems that one day he awoke, having dreamed he was a butterfly. After a moment’s reflection, he wondered if he were instead a butterfly, dreaming that he was a man. How could he be certain?
Rene Descartes was a seventeenth century philosopher, best known for his statement, “I think, therefore I am.” As we saw in the brains in vats scenario, all we experience is the consequence of a stream of nerve impulses. The texture of a rock, the odor of a locker room, the taste of liver, the sight of oneself in the mirror first thing in the morning—all are mediated, rather than direct experiences. The conventional picture of a real, external world is not the only possible explanation for what our nervous system is reporting to us. Rene Descartes realized that it is possible that there is an evil mad scientist experimenting on our disembodied brains.
Scientists place great faith in the evidence of our senses. All human beings do. Most people are skeptical about flying saucers, not because the notion of visitors from other worlds is inherently unreasonable, but simply because no one has yet to produce unquestionable sensory evidence for their existence. Fuzzy photographs and incredible tales by eyewitnesses simply are not enough, for most of us, because we can think of other, more pedestrian explanations for the photographs and the stories of the eyewitnesses. As was said regarding the possible discovery of fossil life on Mars, “extraordinary claims require extraordinary evidence.”
However, the postulation of the brains in vats scenario turns such thoughts inside out. How can you know, by the evidence of your senses, that you are not a brain in a vat? You can’t! There is simply no empirical evidence possible to disprove it.
This, of course, is a significant blow to the idea that everything can be known scientifically. And we’re not just talking about what sort of noises a Veloceraptor might actually have made. If we cannot even know for certain whether the whole of reality as we think we perceive it exists, then our conventional view of things might be outrageously wrong. There must be rather profound limitations on knowledge.
So is anything certain? Descartes’ musings about an evil mad scientist became his starting point in an investigation of how we know what we know. Descartes wrote:
Some years ago I was struck by the large number of falsehoods that I had accepted as true in my childhood, and by the highly doubtful nature of the whole edifice that I had subsequently based on them. I realized that it was necessary, once in the course of my life, to demolish everything completely and start again right from the foundations if I wanted to establish anything at all in the sciences that was stable and likely to last.
Descartes wanted to address the issue of knowledge much in the same way that Euclid had addressed geometry many years earlier. All of
Euclid’s geometry is derived from a set of five axioms. An axiom is a statement that is simply accepted as true as a starting point, with no proof or disproof readily available. For instance, one of the axioms is that “a straight line may be drawn between any two points.” All the theorems—statements that may be proved or disproved—of traditional geometry, are derived from the five axioms.
Thus, Descartes set out to identify a set of facts that were known with utter certainty, that must be accepted as givens, with no proof or disproof of them possible. These facts, then, could become the axioms of his natural philosophy, and all else would be constructed upon that basic, firm foundation.
To Descartes’ dismay, he discovered that practically any statement one could utter about the real world must bear some measure of doubt. Descartes quickly found his ground floor of natural philosophy was little more than quicksand.
“Quicksand” very neatly describes ontology, the study of what is real, since one of the first things one is apt to notice is that the accepted, everyday “facts” of the external world are all disputable. One can almost always come up with a scenario in which unquestioned beliefs can in fact be wrong.
Moscow the capital of Russia?
However, it could be that our government, for reasons of its own, does not want us to know the real capital of
Russia. They’ve gotten all the history and geography books, and all the maps changed to indicate that Moscow is the capital, rather than what the real capital is. Year by year, teachers (for the most part, employees of the government, after all) teach the Moscow falsehood.
Someone might claim they went to
Moscow and saw government buildings that could reasonably be associated with that city being the capital. However, our government is sneaky: it created a theme park simulation of Moscow many years ago and regularly shuttles citizens there to add credence to the Moscow fiction. People only think they went to Moscow, while in reality, they never went anywhere near it.
Of course, most reasonable people would find such an outrageous conspiracy theory laughable.
Perhaps because a less outlandish explanation, a less complicated solution, would seem more likely.
But our big questions remains: is there anything of which we can be certain? Any fundamental truths?
Some might argue for mathematics. Even if one’s first grade teacher were a part of the massive government conspiracy about
Moscow, it seems impossible to doubt that two and two is four. One can, in fact, picture two objects joining with two other objects to form a group of four. This deduction seems clearly true, even if we’re just brains in vats.
However, there are at least two problems with arguing for even this as a core axiom. First: even mathematics might be an illusion. Just because it seems impossible to imagine two and two ever being anything other than four doesn’t prove it’s so. It is obvious that your brain is in a certain state when you come up with your conclusion about the sum of two and two. But what’s to stop that mad scientist who’s playing with your brain from deluding you about arithmetic at the same time as he’s fooling you about the physical world? Maybe two and two is really seven. But by stimulating your brain in just the right way, the mad scientist has tricked you into thinking it is obviously four. Perhaps the mad scientist has a whole row of brains in vats, each one immersed in a different reality, with a different answer to the question of “what is two plus two?”
A second problem with assuming mathematics as an axiom is that it is difficult, if not impossible to move from that to broader beliefs about the physical world. Certainty about mathematics does nothing to tell us what the capital of
Russia might be.
Theories of Knowledge
Epistemology, or the study of the theory of knowledge, comprises the systematic study of the nature, sources and validity of knowledge. It asks the question, “Do we know an independent world or merely our experience?” The possible answers can be broken down into two broad categories with regard to their degree of emphasis on the subjectivity or objectivity of knowledge.
Subjectivistic theories of knowledge answer the epistemological question thus: “No, we don’t know an independent world as the cause of our ideas. We cannot get beyond our experience or ideas, and we cannot speak of a knower experiencing them.”
Objectivistic theories of knowledge answer the epistemological question thus: “Yes, we do know an independent world of material objects and/or transcendent ideas.” In fact, most people from a western philosophical background will answer the epistemological question affirmatively.
So the bottom line is that as a theist, I have accepted God’s existence as a presupposition and then view, or build my concept of reality on top of that axiom. I cannot prove God exists. I don’t think I need to, even.
All members of western civilization hold to certain presuppositions that cannot be proven, such as the objective reality of the external universe, that our senses give us an essentially accurate view of that universe, and that cause and effect are real.
So why do I think what I believe is, in fact, true?
Essentially it comes down to the fact that I find the theistic point of view a reasonable one, based on what I've postulated above; one could also, argue, I suppose, that there are certain psychological reasons that make me predisposed to find it more comfortable than the alternatives. Granted. One could also point out that I was raised in the church, and so that increases the likelihood that I would find the concept of God a reasonable idea. People who have the presupposition that God does not exist have reasonable and rational reasons for believing that, too, I’m sure—and doubtless, like me, there are things that they have gone through in life, their upbringing, or whatever, which has led them to those conclusions.
The reality is, of course, that everyone thinks that they have the truth of some sort, and believe certain things to be so, regardless—even things that they can’t prove. For instance, if the clerk shorts you on your change, you’re unlikely to carry on a discussion about the fuzziness of truth or to argue that the clerk’s truth and your truth are both equally so, and who’s to say if the clerk’s truth is more or less valid than yours. You’ll simply insist that the clerk give you the right change.
You might say that when it comes to the presuppositions, you just accept some things on faith. It doesn’t bother me that I can’t prove everything, and somehow I still manage to function. We all do.