# Descartes: Epistemology in Motion.

Epistemology, or theory of knowledge, is the branch of philosophy that deal with questions concerning knowledge. In particular: ‘What is knowledge?’, and ‘How is knowledge acquired?’. The classical, but not universally accepted, definition of knowledge comes to us from Plato. He described knowledge as ‘True Justified Belief’. Each of these three terms have spawned massive amounts of thought over the years. However, how any of these three qualities is achieved is certainly not agreed on. Say for example that I am asked to add 2 and 4. Now I would, in most cases, quickly add 2 and 4 in my head and come to the conclusion that $$2+4=6$$. This could possibly be considered knowledge since I believe it to be true, it is true, and I can justify it’s truthfulness by the mental mathematics I did to find the answer.  Say instead, I rolled a dice to determine my answer and by chance it came up 6. In this case I still may believe that I came to the right answer, and it is indeed the right answer; however, my method of justification is not correct. It could have just as easily came up 4 and that answer would be wrong. Rolling a die does not count as justification in this case, even if I strongly and fervently believed that somehow dice were capable of determining simple mathematical expressions.

Descartes took seriously the idea that anything logically built on a true statement must also be true knowledge. He famously spent a great deal of effort trying to find a single statement that absolutely must be true. That even given a thousand years of academic study, nobody could ever prove this statement wrong. The statement he came up with is the famous, Cogito ergo sum: I Think Therefore I am. If he doubts that he himself exists, then there would be nothing doing the doubting. Therefore he must exist. This does not prove that he exist as a human, merely that he exist as a thinking entity. The rest of the argument is as follows. In it’s incredibly condensed form.

After concluding that he himself exists, it falls readily that he is capable of determining truth. He determined this truth by finding a statement that cannot under any circumstance be doubted. Therefore, he concludes that any statement that under any circumstance cannot be doubted must be true. This idea he names ‘Clear and Distinct Perception’ (CDP). He then CDP’s the ‘Causal Adequacy Principle’ (CAP). The CAP states that every object must have as much or more reality as the idea it produces inside his head. So the image of a chair that he remembers sitting on yesterday, is less real then when he actually sat on it. Finally he uses the CAP to CDP’s god’s existence. The idea of God in his head is that of a perfect God. CAP requires that everything in his head came from something more real then the idea it produced. The idea of God in Descartes head is one of perfection. Since nothing in the world is perfect, he could not have gotten the idea from something in the world. Thus, he must have gotten the idea from God. Therefore, God exists and is responsible for giving Descartes the ability to CDP truth.

Did he build truth? Probably not. The most suspect portion of his proof is his ‘Clear and Distinct Perception’. Sure I can’t doubt my own existence, that doesn’t mean I exist. Especially considering existence is such a poorly defined term term to begin with.  However, CDP as a whole is suspect. Just because he has no reason to doubt his conclusions at the current moment, does not  mean it won’t at some future point be open for doubt. I gave a perfect example in my previous post. This aside, Descartes does lead to a perfect discussion of two very important concepts in Epistemology: Foundation, and Coherence.

The problem inherent with arguing from foundation, like Descartes did, is justifying the next true statement. Let’s grant to Descartes that he does exist. Let’s pretend that this statement is true in it’s purest sense. Now what? Descartes existence does not imply anything. Let’s say we used Descartes existence to prove some statement X. The skeptic can always ask, “How do you know that Descartes existence proves X?” You will be forced to give an explanation, that has nothing to do with the existence of Descartes. This very quickly moves the argument off of the firm foundation Descartes was trying to build. True justification is then something that is also necessary to have a foundation. Not only do we need an unquestionably true statement to build off of, but we also need an unquestionably true system of proof that can expand on our true statement. In Descartes case he choose CDP as his unquestionably true system of justification. However, it is far from unquestionably true and therefore fails it’s own criteria for truth. It is therefore worthless.

Coherence is the idea that statements are true if they cohere to other true statements. For example say I knew there was train track at a station in Edmonton, and a station in Calgary. I also knew that a train drove between the two station regularly. I can conclude that there is also track between the two stations because it coheres to the other true statements in the system. The trains cannot travel between the two stations regularly if there is no track between them, so it must be true that there is tracks between them. Similarity if we knew there were tracks in Edmonton leading to Calgary and a train traveling between them, we would be justified in believing there were also tracks in Calgary. In this case nothing is really our foundation, it is just a whole system of facts that are either true together or false together. If I was lying to you and there really is no train, (which unfortunately I am) then the whole system is false. Although, it does not mean there is no track in Calgary, it just means we cannot use anything in this system to prove there is track in Calgary.

Coherence is often given as a completely separate theory of truth. Theories of Epistemology are often given as either Foundationalist or Coherentist. Personally I don’t think separating the two is helpful. Coherence requires you to have some accepted system of justification already in place. So that certain facts can logically lead to other facts. It still requires us to have some form of foundation to cohere too.  The singular difference is in a Coherentist philosophy we don’t have to prove that our foundation cannot be questioned, only that it fits with everything else we accept as truth. The fundamental problem with Coherentist philosophy is that Coherentists often build systems that are completely self consistent but have nothing to do with reality. In fact Mathematics is in general both a Coherentist system and a Foundationalist system. We build ideas that cohere to each other from a constructed foundation. However, In general this ‘axioms’ can be back proven using the results that they produce, meaning we can build up multiple foundations that result in the same mathematical systems. The fundamental justification for our foundation being that we simply ‘assume’ them to be true. Descartes would hate this because he wants some absolute sense of truth. In my opinion assuming something to be true, and CDP’ing something to be true only vary by the name we assign to them. This creates a new system of ‘contextual truth’ which will be discussed in the next portion. However, that leaves the most obvious question, “What does this have to do with anything?”. Anyways we look at it, what we talk about must be relevant. So no matter how we define our foundation, or our system of coherence, we still need something to tie it to the real world.

So then if we throw away both the impossible ideal of having a unquestionable foundation, and the false notion that ideas that ‘fit’ must be true. The only thing we have left is the scientific method. When reality sinks in, what we are truly interested in is not a Epistemological system but a Scientific system. Let’s take Newton’s laws of Motion as an example. Newton gave three laws of motion that serve as a foundation for classical physics. From these three laws and using mathematics as our form of justification, we can predict the outcome of many scientific experiments. Newton’s laws form a purely mathematical system, in order to make it a physical system we require something else: experimental data. In reality, experimental data forms the foundation of any real physical system. If the mathematical foundation, the three laws of motion, do not cohere to the physical foundation, our experimental data, the theory is wrong. So the Scientific Method is a constant system of guess and revision. We guess a system, check it against the experimental data, then revise the system so it coheres to the new data. If some of our old assumptions no longer cohere to the new system, they have been proven wrong and can thrown them out. There is no reason why the skeptic cannot question the scientific method. If Descartes CDP doesn’t give us truth, then what is it that allows experiments give us truth. Ironically my reply to this is fundamentally foundational. I need to make three assumptions in order to continue this paper. The first is that I exist, the second is that the universe exists, and the third is that I perceive the universe through my senses. So if I want to learn something about the universe, then any system I make inside my head must cohere to the observations I make via my perceptions. My perceptions then are the only possible way to learn anything about the universe. Should the skeptic still doubt that this method tracks truth, then there are only two remaining possibilities.

The first is that I have already won. If there exists any truth external me, then that truth is unknowable. Therefore, God’s existence cannot be ruled out. Fortunately this solution is far from satisfying, and my guess is it isn’t satisfying to anyone else either. So for now we shall assume that perceptions can lead us to external truth. The other option is that all truth comes internally. In this case every true statement about the universe is already inside of me, and I do not need perceptions to get at them. Unfortunately, this also assumes that the universe itself is a subset of my mind. Eventually, this pit leads to solipsism. This is an idea I reject, although I can’t explain why at the present moment. So for now I shall leave it as a topic for another day.

I am willing to accept that any of my three assumptions could be false. If this is true, then anything that comes after is false as well. Should such a proof ever erupt, I believe we will lose much more then my simple philosophy.

Finally there is only one more complaint I shall allow from the skeptic. That while sense is still the only viable system for determining truth. It is still possible that I could make up a system that coheres perfectly to every observations my senses have made or will ever make. Yet that system is still not the true system. This idea is fundamental to the concept of Virtual Reality, but it is not something I can go over at this time. So once again, I shall leave it as a topic for another day.

Next: Truth, it’s definition, or lack there of.

PS: It is actually rather entertaining to try and convince someone that they or the universe don’t exist. If anyone is actually successful in doing this, please tell me. Might be a good story.