My own interpretation of that is that I know what I know from direct experience. I perceive a mental image, therefore I know the mental image exists. Whether it accurately represents (the cat) it's physical counterpart is another question all together....
The difference between those who espouse outlandish theories and those who follow the agnostic/atheistic system can be boiled down to a very simple point. It's not about how well the mental activity represents the cat, but about the
understood value of that activity itself.
I was going to explain this to Interesting Ian but as he's remarkably unaware of just how ironically uninteresting and uninterested in anything but his own prejudices he is, I couldn't be bothered. But you seem to be more interested in actual understanding, so here is the explanation.
When an event occurs, the brain and body both react in a certain way towards that event; some of this is biologically determined, some of this is random, some of this builds upon prior reactions and developed tendancies... but for now, let us assume a blank slate reaction. Let us say we are seeing a cat for the first time.
The experience of the cat may come from outside of ourselves, but the reactions to the cat are entirely internal to us. Our eyes see, our brain interprets, our feelings respond.
Now, the mind/body reaction to that cat can be stored in Memory by the brain... It doesn't always store it perfectly, as Memory can be lost, and it also stores it according to what ever value it judges the initial experience to have, so it tends to forget things valued unimportant... But when it's something which is understood as important, it's retained as accurately as possible.
And when also it's judged important, more than just "cat" is remembered... If it's a scratching biting cat, the brain might file it in a very important area of memory, and then connect that up to the areas of memory dealing with commands to feel caution, fear, worry etc... So if "cat" memory is triggered, "feeling of caution" is triggered too. If it's a happy purring suckling cat, important memory because pleasure is important but "cat" gets attached to attraction, interest... etc. And just a cat passing on the street? Just into "cats exist, so what?" memory storage.
The point is that the way we percieve things we are not currently experiencing depends entirely upon the way the brain has laid down it's neuronal pathways... The ability to percieve of a "White Cat" depends entirely upon how important that combination of terms is. For me, it means nothing, because I've never known a White Cat, and I have no strong association with the color White by itself (It doesn't mean purity or goodness or any such thing to me). But if you had said "Tabby Cat", not only could I imagine such a cat, but it would trigger very, very strong memories of a particular cat, doing particular things... things which I could almost feel as if I was with her again. And I DO feel it, because of the way in which my mind has been wired up to trigger memories of the way in which my feelings reacted to that cat; and so I feel those things (or as close as memory and appreciation allows me to get) again.
But there's more... and this is where the difference between believers in the super-natural and the objective, scientific world lies. This process HAS to be considered "real", because otherwise it doesn't work. Take fear for instance... if you are faced with an uncertain threat, and can say "Oh, but the fear I feel for what might be there isn't genuine fear, just the memory of a past event", then your survival chances are much lower than if you trust your fear is genuine and treat it as such (overall this is... mostly the monster under the bed isn't there... mostly).
Now, the scientific amongst us still feel fear, wonder and so forth, but we know that it doesn't necessarily match objective reality; The thought of a particular "cat" exists, and can be powerfully felt, but it exists only inside our heads... because it is a product of and dependent upon the existence of our minds.
The believers however have simply taken that need to trust their mental functions to a higher degree. They not only feel the "Cat", but believe that feeling must be REAL in a sense which goes way beyond pure material determinism, beyond evolutionary utility. It simply HAS to be telling them something TRUE and DIVINE that they can think in such terms...
I've already said I don't imagine "White Cats" that well. The fact that you thought it would be a good example Filip is merely proving my point... Because you imagine such a cat so well, you assume it holds true for more than just your own mind... that we can imagine the same as you, respond as powerfully as you do, and see the lesson that such an imagining teaches as clearly as you. Everyone thinks like this to a certain extent about their own beliefs... "if I can explain why this movie is so good, you'll appreciate it too", and so on... but the truth is, understanding simply doesn't work like that. It's entirely possible to imagine a mind which doesn't imagine much of anything, if given sufficiently dull stimulus... Such as being locked in a room when they are born, with only Interesting Ian's wibble for reading material , for instance. Such a mind wouldn't react to your White Cat example at all.., not unless it was a White Cat complaining about S
Keptics, anyway. What seems so evocative to you would completely pass by such a person. So where does this "White Cat" exist in any objective sense? It exists only in how each individual mind chooses to define, or not define it.
Let me put it in mathematical terms; All minds are built from very simple addition... X + Y = Z. In your example, you've asked us to imagine X = "White", Y = "Cat". But whilst our minds may be performing exactly the same formula, our result for Z is going to be different, because X does not = "White" for us, or indeed perhaps "White" for us does not even = "White" for you.
This is what makes me laugh at people like Lifegazer so much; they really think they are looking at Life, the universe and everything... but what they are really doing is staring at nothing more than the insides of their own mind, minds which have extended their own internal understanding out onto the exterior world. "It works like this inside my head, so it works like that outside it too." But it doesn't, and never will unless you find a mind which shares your own personal understanding of the variables.
In a way Filip, you are doing the same. I don't doubt that you have a much more sensible understanding of what the mental image of a "White Cat" means... but you are still making the same mistake as the lunatics. You assume that no physical mechanism can be responsible for the moving, powerful Thought you can experience, because you have a sense of wonder attached to the process of Thought itself; But as others have already mentioned that modern science is starting to close in on the physical mechanisms by which Thought operates within the brain... It may never be able to 100% describe a human mind, because it's the mind's very ability to design and redesign it's own blueprint which allows us to be so intelligent... or in some cases, so horribly insane: You cannot say that "This area of the brain is where so and so individual memory is always stored", because for the individual, it may not be. And there's no guarantee where each memory will be connected too either. Lifegazer's mind probably looks like tangled string, each thread emblazoned with sentances like "why can't people understand me?" and "I could perform miracles if I want, I just don't want", all wrapped around a huge, simple core which merely states "This Proves God".... However, the materialistic mechanism remains the same, even in such a mind, the sums are always totalled up in the same way, it's just some of us think 2 + 2 = 5.
