Descartes asserts that because something can be doubted, somebody or something must be doing the doubting. Therefore, thought exists. “I think therefore I am.” The very fact that he is doubting proves an existence. Thus Descartes concludes that he exists, but in what form? He perceives his body, and the world around him through the use of the senses; however, these have previously been proven unreliable. The senses can be manipulated and confused. So Descartes concludes that the only indubitable knowledge is that he is a thinking thing. Thinking is his essence as it is the only thing about him that cannot be doubted.
What follows is a case based on a premise of Cartesian Skepticism as to why the physical sciences are based on a fundamental element of faith, and that one doesn't accept science except on the basis of faith, obscure though it may be. There are many other arguments as to why this is so, but this is perhaps the easiest to communicate.
Take for a moment a “Matrix” type scenario – more importantly, imagine that you are in “The Matrix”. The Matrix creates and controls the variables by which everything you recognize as true seems true to you. The Matrix creates for you your conception of your body. The Matrix has arbitrarily set the constants of your universe. The Matrix is the sole place in which this dualistic conception of matter and energy exists. Taken in its entirety, every single thing which your senses tell you is an utter and complete fabrication, a fallacy, a cosmic joke being played on you.
What’s real outside of this matrix scenario is this – you’re a brain in a vat. Except, there is no brain and there is no vat. You’re a shapeless, massless, dimensionless something that we can’t quantify because the illusion of The Matrix has given us no terms in which we could discuss or conceive of what you really are. The reality of the universe is one that belies temporality, matter, motion, rest, necessary causality, in fact, it doesn’t even adhere to the laws of reason. In this dimension (if we could call it that), the “true” dimension, things don’t even follow reasonably, as we know reason, because it is wholly different. So what is actually “real” is utterly and completely alien to what we perceive as our reality. In short, this is a universe where all of the conventions of science as we know it are completely non-applicable, our library of scientific knowledge is false, and in general, science as we know it would need to be almost completely revised to be anything but an exercise in futility in this “true” reality.
Now, here is where I say that science is based on a fundamental article of faith.
The physical sciences are based upon, rely upon, the laws of reason and the idea that observation will yield for us some sort of truth. In the above example, I’ve (Well, Descartes has) given a case where all possible observations of science, all the fruits we garner from this, are reflective of nothing more than an illusory falsehood and don’t actually reflect the true conditions of our existence – or at best, only reflect a very small portion of that existence, and one which (by conventional standards of truth and falsehood) we are not inclined to say is reflective of any objective truth, and only show us the patterns within our hallucinations, but not the truths of our hallucinations. Some say that science reveals truths for us, and science is not taken on faith, however, by taking the idea that science can reveal truths of the universe, we are showing faith that the above case is not true. So science is based on a fundamental article of faith. Now, saying that it could be made possible that the rules of reason could be rendered non-applicable is actually my taking a bit of liberty and going beyond the realm of Descartes’ argument. We can apply this same skepticism to almost any reality conceivable. Change the scenario to one where all of the laws that science has identified, every element on the periodic table, gravity, even causation are creations of the Matrix, and in fact none of them apply to the ‘real’ world around you. Thus, the laws of reason can still be applicable within the known frame; however all of the knowledge garnered from scientific methods and observations are fallacies because they happened in the false reality rather than the real one. And in the real world none of them would hold true.
The case of Cartesian doubt, is not one that is based upon specific, obscure, philosophical methods that are alien to science. It is founded on reasonable derivations of what reason would define as possible. The purpose is simply to show that one has rational to doubt what can be generally thought of as reasonable conclusions based on what we perceive around us. If human capability were greatly expanded, the premises for Cartesian doubt could quite plausibly fit into the realm of science as something that must be tested and a problem that must be solved - an experiment. I hope it’s clear, Cartesian doubt is a premise founded on reasonable grounds by a reasonable man, meant to be entirely within the laws of reasonable derivation that govern the sciences – in other words, Descartes played by the rules of science to show that there was room for doubting the reasonable and experiential grounds which the sciences find their basis in.
What does this all boil down to? Descartes showed us a case, reasonably conceived, that seemingly falls well within the realm of reason, by which we could have realistic doubt about anything the physical sciences reveal to us. If one wants to maintain that science is not based on a fundamental article of faith, you have to show one of several things: One, that Cartesian doubt is outright impossible – and you must show that it’s not simply likely impossible, but is impossible, or you fall back into faith. Or two, you have to show that Cartesian doubt is in fact some philosophical sleight of hand and is somehow not even applicable, and that though it may be true, we aren’t operating on faith that what science tells us is true. If one of these two things cannot be said “The case of the Cartesian Matrix is true, and it does leave grounds for doubt that the sciences show us anything accurate at all” and in doing so, you admit that you accept scientific knowledge on faith.
Now, even if Cartesian Skepticism is a valid case, this is not reason to abandon science nor hold it in any less regard than we do. It simply changes the premise on which we value science. Whereas many now perceive science as some necessary engine to truth, acceptance of Cartesian Skepticism would mean that we admit that we accept it on some level of faith and instead value it because it is the source of all pragmatic motive and purpose. Even in holding beliefs in science that we admit may be false, we appreciate the benefits it gives us and that this belief does give us a very comfortable, if conditional, premises on which we understand our world. It is not a statement of the uselessness of science, it’s simply a recognition of the ambiguous nature of human existence and that even with seemingly elegant and comprehensive tools that science affords us, there is room for doubt, and we still take even seemingly systematic systems like science on the basis of assumptions, and with a grain of faith. If anything, Descartes was simply pointing out the gap between the idealistic of human nature and how we apply these ideals onto reality, showing that there was always a bit of slippage leaving room for doubt. It is important to look at the implications and contradictions within the belief structure that science provides the, it can not be taken as a vehicle of fact and to fact, but that doesn't belittle the practical applications of that belief structure. Indeed, we should value science as a means to pragmatic ends and not as a will to truth.
