(April 18, 2012 at 8:14 pm)FallentoReason Wrote: ...independenty establish how it came about using our cognitive faculties. That's the thing, you cannot escape the fact that by default it is through our cognitive faculties that we're trying to justify our cognitive faculties..
Can it be said that empirical evidence can be used, despite the fact that, again, it is through our cognitive faculties that we process it?
That explanation was given in post #11. I'll requote it here for your convenience and we can discuss any issues with it.
Quote:Whether or not we actually have the capacity to know the truth cannot be determined by where that capacity came from. The only way to determine it is by finding out if that capacity actually works.
Now, how do we determine if we actually have that capacity or not? You do it by measuring your knowledge against reality and seeing if measures up. To start measuring, you first need a starting point.
Let's start by asking how do we determine truth? Forget for a moment whether we actually have the capacity to know the truth and ask how any entity having this capacity would determine what is true. It would check the statement made against what is real. Suppose the statement is "an apple is red", then the entity would check whether a real, physical apple is actually red or not.
Now, let's go a step further and look at the example you provided. "Can X equal non-X"? Suppose, in reality, X can equal non-X. If this is possible in reality, then something can and cannot be itself at the same time. A statement can be true and false at the same time. This would mean that there can be no such statement such as truth. Then it wouldn't matter if you have the capacity to know the truth or not, because there wouldn't be such a thing as "truth" to begin with. Therefore, we can establish X is not non-X as a basic fact of reality that doesn't depend on whether we know it. Incidentally, this is the Law of Identity, the basic premise of all logic.
So, we've determined that for there to be such a thing as truth, the X can only be equal to X and since we have used our reasoning faculties to determine this, we can say that they work pretty-fucking-well. We have established two lines of reasoning here:
1. If there is such a thing as truth, then we have the capacity to know it. (as demonstrated here).
2. If there is no such thing as truth, then there is such a thing as truth (basically a self-refuting and meaningless statement).
Does this clear up why we safely say that our rational faculties actually determine the truth irrespective of where they came from? If this is too complex, there is a simpler argument, though I don't think it'd be as convincing. I'm presenting it anyway.
Can you actually know the truth?
1. There are only two possible options. Either you can know the truth or you cannot know the truth.
2. If you cannot know the truth, then all statements of knowledge you make are false.
3. This includes the statement of knowledge that "You cannot know the truth".
4. Therefore, that position is essentially self-refuting and the only option you are left with is "you can know the truth".
