Okay, these are my opinions on the questions (and yes, I am going to use some Foucault, if u dun like him, deal with it

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1: Is language a baseless system?
I would have to say yes. The reason is this, I wasn't refering to reality as the base, I as refering to anything that would count as a real foundation. "What would this sort of foundation be?" you ask, well, it would be anything that is outside of the system of language. But, it cannot be a system which itself is baseless or foundationless. For example, I would not consider intersubjective agreement a system wth foundation for a few reasons. First off, subjectivity is a foundationless system, secondly, because we can never surely know what another percieves without actually being that person, the agreement is falsified, I might of had something in my mind that I was agreeing on, but you have something completely different, therefore, it is a fallacious agreement. For example, I might agree with you that the definition of word "x" is "y" but none of us agreed what the definition of word "y" was, so itwas an artificial agreement, and thus, false. Let's plug in the "numbers" If I agree with you that "enraged" means "angry", but I think that angry means "pickle" and you think it means "orange" we never really agreed on what enraged means. When you think of it, can you really define any word? What I would think it comes down to is what in the end we would percieve the word means, but, since we can never really convey this, and like I sad, since we can never truly agree on this, I would say that language is a baseless system.
2: Does discourse shape reality, or even create reality?
This is of course, as you predicted Brimshack, where Foucault comes into play. Again, I answer yes, but only to the first part. Here is a quote from the book "Understanding Foucault" (yes, scoff all you want, I'm just trying to give an example that is easy to follow) the stuff in parenthasees (i dun know how to spell it) inside of the quote are comments that I put in, except for the last one.
"An example (of how discourse shapes/creates reality) could be something as mundane as records documenting the movement of ships into and out of a harbour over a 50-year period. A study of such records might find that, from a certain time, referances to piracy began to crop up-or to enter discourse. What such references would show is that piracy had bcome a problem for that harbour's shipping authorities. It may have been the case that acts of piracy had occured previously, but it is not until it enters the discourse of those records that it has a status within the practices and concerns of the shipping authorities. Certain events might have occured quite regularly-ships attacked, people killed, and goods stolenby men with wooden legs and parrots on their shoulders-but until these things were recognized as constituting something called "piracy", they would have been ignored, and given some other discursive explanation (say, rebellion, or acts of war, or just wild Firday nights).
I don't think I can give a better example, so yeh, I think that would be why discourse shapes reality. I would say it dosn't create reality, as in, It is not what reality is solely based on, because, if everyone was silent everything would not suddenly blink out of existence, no, I think reality is based on perception, which brings me to my last point.
3: Is perception a scewed way to base reality on, do we base reality on perception?
I would say yes to both. Basically for the same reasons stated by Wryan. But I'll go further, if reality is based on perception, which is scewed, does reality then exist. I would say that percetion creates reaity, and not the other way around. The only reason I say this is because I for one cannot know there is a reality, I am sure though, of my perception, basically like the ruler of the universe (reference to the Hitchhiker's Guide To the Galaxy four part trilogy, lol). Where I think Wryan goes wrong is when he says "Regardless of whether or not my perception is flawed". There is nothing to base your perception on to determine whether it is flawed or not, therefore when you fall, your perception is making that reality, and if it doesn't, then your doctor is making is own reality when he thinks you are in critical condition. For example, there was a case of this women who has lupis, a disease where your immune system starts attacking your body, she wasn't expected to live for many more months, let alone years, and she lived for like ten more years after going to a witch doctor and getting a curse removed. Now she obviousy created a reality where the curse was the cause of her ailments. I'm not going to arrogantly reduce it to "I know reality doesn't exist due to that example" because it is obviously a very complicated thing, a possibility is we create rules for our own realities, but, the truth is, it's tricky, if reality really doesn't exist well, there are a lot of unexplained things, things that couldn't be explain because there is no reality to use to explain them.