I don't know what you mean, but if the board is 4 feet long, it's really 4 feet long. This is not a matter of a appearance, it is a matter of reality.

Unless we have a reason to doubt, why would we? Extreme skepticism leads to infinite regression, and can actually manifest itself as a form of paranoia.

Just because it's logically possible we could be living in the Matrix, doesn't mean we should doubt that we are living in reality.

But the fact is we don't know we're perceiving anything accurately, again, check out Decartes' total deception argument, or just watch the Matrix! In either scenario what we are seeing is not reality, but it looks just like reality, so we simply cannot tell the difference.

Kant also says we can't even talk about reality, because we have our own conceptual scheme which means we project certain qualities onto the world that aren't really there. For example, the fact that things do get smaller as we move away from them, this doesn't happen in reality, but if our minds didn't do this, the world would be unperceivable. He uses the example of rose tinted sunglasses that we can't take off, our minds are like the sunglasses, they make the world seem different to how it really is.
I'm not explaining very well... try this In As philosophy; how does Kant's conceptual scheme work? - Yahoo! UK & Ireland Answers



This is true, and some philosophers do say that we don't need certainty in order to know something. However, the definition of knowledge is a true proposition, and if we can't really say whether the proposition 'there are birds in trafalger square' is true with 100% certainty, can we really say we know it?
I would say no, but for all practical purposes, we will say we do.

Its really one of those philosophical dilemmas which is impossible to answer, but it really doesn't affect the way you live your life. Personally that's why i prefer ethical philosophy, but i'm studying this stuff right now and i have an exam in May, so i thought i'd get some practice in!

But if Kant says we cannot even talk about reality, I certainly disagree. What rational person wouldn't?

Kant was grounding objectivity. Direct realism is equivalent to solipsism. Of course objectivity is grounded in a practical sense by language. Direct realism is not absurd because it unconsciously is founded on language, which can only evolve socially.

Kant was grounding it logically. The average person is close enough to reality for their everyday needs.

there's a brilliant one in my philosophy text book, but unfortunately that can't be copied and pasted onto my PC... yet, here's hoping!

Yes, if you are an average person you don't need logic. Who claimed that direct realism is absurd?

Size is relative and subjective you will not truly comprehend the true size of an African Elephant unless you stood right next to it

---------- Post added 03-03-2010 at 04:34 AM ----------

Size is relative and subjective, you will not be able to true size of an African Elephant unless you stood right next to it.

Please go to the link below and you will see exactly what I mean

i'm simply saying we can doubt it, and therefore can never be certain.

How about:

Size is relative, you cannot comprehend the true size of an African Elephant.

if size is relative then the size of the African Elephant can compared to an atom no matter where you are in the Universe

if size is relative then the size of the African Elephant can compared to an atom no matter where you are in the Universe

if size is relative then the size of the African Elephant can compared to an atom no matter where you are in the Universe

if size is relative then the size of the African Elephant can compared to an atom no matter where you are in the Universe

What is the size of an atom?

At what distance must an object be from a perceiver in order for its appearance to equal its real size?

--

I am not sure what you mean. What I was saying is that there is no objective frame of reference to judge size from.