Skepticism and Rationality

[pcg2]

I am taking a philosophy course, right now focusing on Descartes’ Meditations. There’s a confusing passage in the first meditation that begins:

“… there is an all-powerful God who made me to be the kind of creature that I am. How do I know that he has not brought it about that there is no earth, no sky, nothing that takes up space, no shape, no size, no place while making sure that all these things appear to me to exist?.. how do I know that God has not brought it about that I… go wrong every time I add two and three or count the sides of a square?..”

Descartes quickly advances a number of skeptical arguments. The arguments seem to be designed to convince us that we don’t know (for certain?) even the “transparent truths” of elementary arithmetic and geometry. The argument goes something like this:

1. I don’t know that God has not brought it about that I go wrong every time I add 2 and 3, etc. (God has not brought it about that I believe 2+3 make 5, when in fact 2+3 don’t make 5?)
2. If I don’t know that, then I don’t know (for certain) that 2+3 make 5, etc.
3. Therefore, I don’t know for certain that 2+3 make 5, etc.

Premise 1 states that there’s something that I don’t know. The argument is supposed to show that if I don’t know that one particular thing, then I don’t know (many) other things as well.

I’m stuck. It’s the first premise that bothers me. How do we know that God hasn’t “tricked” us into this kind of reality? I’m not a skeptic, but I can’t seem to find a way to refute the first premise Any comments/refutations/assistance?

 

[Prodigal_Son]

I’m stuck. It’s the first premise that bothers me. How do we know that God hasn’t “tricked” us into this kind of reality?

You’re conflating two concepts: knowledge and certainty. We cannot be *certain *that we aren’t being tricked, but it does not follow that we do not know it. But this brings up an interesting question: what do you think knowledge is?

 

[Magnanimity]

I am taking a philosophy course, right now focusing on Descartes’ Meditations. There’s a confusing passage in the first meditation that begins:

“… there is an all-powerful God who made me to be the kind of creature that I am. How do I know that he has not brought it about that there is no earth, no sky, nothing that takes up space, no shape, no size, no place while making sure that all these things appear to me to exist?.. how do I know that God has not brought it about that I… go wrong every time I add two and three or count the sides of a square?..”

Descartes quickly advances a number of skeptical arguments. The arguments seem to be designed to convince us that we don’t know (for certain?) even the “transparent truths” of elementary arithmetic and geometry. The argument goes something like this:

1. I don’t know that God has not brought it about that I go wrong every time I add 2 and 3, etc. (God has not brought it about that I believe 2+3 make 5, when in fact 2+3 don’t make 5?)
2. If I don’t know that, then I don’t know (for certain) that 2+3 make 5, etc.
3. Therefore, I don’t know for certain that 2+3 make 5, etc.

I’m stuck. It’s the first premise that bothers me. How do we know that God hasn’t “tricked” us into this kind of reality? I’m not a skeptic, but I can’t seem to find a way to refute the first premise Any comments/refutations/assistance?

I would advise you to read Etienne Gilson, specifically The Unity of Philosophical Experience and God and Philosophy. It is a profound mistake to try to understand Descartes outside of his historical context. Descartes arrives in the history of thought at two critical junctures: the breakdown of Medieval philosophy and the rise of mathematics/ science.

Descartes was himself a particularly gifted mathematician (ever hear of Cartesian coordinate systems?). But, the basic fallacy that plagues his philosophical thought is that he believes that the same methods used and type of certainty one can have in math, he can also have in philosophy, even first philosophy. How does he arrive at this certainty? Well, like a good mathematician, Descartes tries to get down to basics in philosophy in the same way one might do the same in geometry: what are the “indubitable axioms” (see the mathematical mind at work?) of philosophical thought, he wonders.

So all the thought games, hypothetical scenarios (like you reference) that he plays out in the Meditations are a part of that process of trying to reduce himself to the indubitable truths. Once/if he finds them, he will be able to build on them and work out a philosophical system that is as airtight as Euclidean geometry!

Two main criticisms came at Descartes during and after his time. First, philosophy begins with reality, not skepticism. So, in response to premise 1 that he gives, the question is, rather, what reason do you have for believing that God has brought it about that you err…? Does he have any reason at all for believing that? No. So, what’s the point of the thought experiment? It’s what I list above-his attempt to make philosophy operate according to the same principles as math. The only thing going on here is his attempt to reduce himself to the indubitable truths. Gilson calls this fallacy a “mathematicism,” I believe. Trying to make any and all disciplines operate according to the same rules as math is a profound mistake.

Second, and I don’t think this is a spoiler for you…you know where Descartes is going to end up, right? His indubitable axiom? You’ve heard it before, “I think, therefore I am.” His critics said he reached to far. At most, Descartes could affirm the following undeniable truth from his thought experiments, “Thinking is going on.”

I could keep going here, but then I’ll end up doing a lot of your own critical thinking for you, and that’s not good. The main point with Descartes is to recognize his historical situatedness as being an enormous factor on this particular mathematician doing philosophy.

Read Gilson, and you will do yourself a world of good here.

 

[vz71]

We cannot be *certain *that we aren’t being tricked, but it does not follow that we do not know it.

Tricked or not, does it really change the game?

I am driving at night and believe I see a deer jump in front of my car.
It could be a deer, it could be a trick of my headlights and the shadows.
Do I continue merrily on my way because it could be a trick?
Or should I take a course of action prudent to the scenario likely to have the most consequence?

While we are thinking about this…I did slow down, it did turn out to be a trick of the light, and it ultimately did not matter if it would have been a deer or otherwise.

 

[Prodigal_Son]

Tricked or not, does it really change the game?

Nope! I agree 100%.

 

[chrysostim83]

Perhaps it could be argued that the truth of the statement “2 + 3 = 5” is more certain than the possibility of God’s tricking us into doing our sums wrong. After all, when you try to think of such a possibility, nothing clear or distinct comes to mind.

Overall, however, bear in mind that the early parts of the Meditations are meant to be disturbing. Later on, Descartes will arrive at certainties, and in fact, he’ll refute the very proposition that’s bothering you.

 

[psify]

You’re conflating two concepts: knowledge and certainty. We cannot be *certain *that we aren’t being tricked, but it does not follow that we do not know it. But this brings up an interesting question: what do you think knowledge is?

Knowledge is not a natural kind. So ultimately it doesn’t matter how we define it. Say we have KnowledgeA which is defined one way, KnowledgeB, defined another way, and KnowledgeC defined yet another way. We can discover that KnowledgeA has certain properties and consequences and KnowledgeB certain other properties and consequences, maybe with some overlap, etc. And whether we choose to annoint KnowledgeA,B, or C as “Knowledge” just affects our dictionaries and language.

KnowledgeA might be more interesting, useful, or beautiful than Knowledge,B or C, but just as a rose by any other name smells just as sweet, it does not matter which thing (if the definition are all coherent, they would describe three things) we call knowledge. It only matters that we understand each thing as it is.

A similar thing can be said about “god”…

 

[Prodigal_Son]

Knowledge is not a natural kind. So ultimately it doesn’t matter how we define it. Say we have KnowledgeA which is defined one way, KnowledgeB, defined another way, and KnowledgeC defined yet another way. We can discover that KnowledgeA has certain properties and consequences and KnowledgeB certain other properties and consequences, maybe with some overlap, etc. And whether we choose to annoint KnowledgeA,B, or C as “Knowledge” just affects our dictionaries and language.

Yes, I agree that knowledge is not a natural kind, and that we may define it how we like. For simplicity’s sake, philosophy has often defined knowledge by the conjunction of true belief and relevant justification. This conforms to the usage of the word in common English. If one wishes to define “knowledge” as “certainty”, well then it would be impossible to conflate the two concepts!

A similar thing can be said about “god”…

A similar thing can be said about anything. Before we had “discovered” the elements, we had a concept of elements which we “grafted onto” our observations. Just so, we develop a concept of God and then we look into the world to see if this concept is exemplified. Our concept will shape our perceptions of the concept’s existence.