Are you trying to suggest that the human mind has somehow inevitably to create something that doesn't really exist out there if it is to understand the world at all?!
Sort of, but what could it mean to say that something exists independently of a model--a web of associations--that a mind creates to give it meaning? The things that we interact with are necessarily built up out of many different levels of abstraction.
And then the question becomes whether we really know we step into any actual river or if we merely think we're doing it. We're only thinking we're stepping in and it's only into our mental abstraction of a river.
Again, what could it possibly mean to say that something is not an "actual river" independently of the abstract knowledge that tells us what a river is? That river might not exist as a "thing" to a bat, a fish, or an insect, because those organisms don't interact with such a body of water in the same way that human beings do. When you sit down, does your "lap" actually exist? What could it mean to an organism that had no experience of legs and joints?
As I understand it, there's a clear sense that we have of a real river, which is whenever we somehow experience one. Then we have memories of such, and then the concept of river, and then maybe abstract representations and theories about rivers. It's apparent that we are able to distinguish between all these things (well, maybe not
everybody around here apparently). So all these different things, things we assume are either physically real or just something within our mind, provide the sense for whatever we say about what we think of as an actual river. If I talk of a real river, I'll
imagine one and in a way that seems to me directly related to what I remember of me watching the river Seine here in Paris or some river elsewhere.
I take it that we all have an impression that our perceptions
are the real material world. Science tells us it's just an impression somehow inside our brain, which logically leads to observe that the scientists' impression that human beings have brains is also just an impression. This doesn't mean there is no brain at all, only that our impressions are likely mere mental model standing for whatever there is out there. All this makes sense, at least as long as we don't reduce the model to that of a purely material world. This also doesn't mean somehow Dualism. It just means that it's coherent to think in terms of what we do know, i.e. broadly our qualia, which because we know them necessarily exist, and what we don't know but believe exists, which may well exist, and why not, but not necessarily and even most likely not much if at all as we imagine it, or even as scientists model it. That much makes sense to me. It's a kind of epistemological dualism, but I'm not even insisting that's definitive. If anybody can offer me a coherent view of reality, one which is both consistent with my subjective experience and my sense of logic, then fine. But for now, all I see is either people I can broadly agree with, or hardcore materialists, or hardcore physicalists, with no argument and not a care for logic.
So to me, when we talk of a river, an "
actual river", it may be very different things, not just the "
abstract knowledge" version. It may be our perception of an actual river, i.e. we take our perception to be the actual river, or an abstract idea of a river, one that perhaps we think to be the best we can do as a model of what rivers are even when we're not here to look at them. So, we seem to be more like processes than somehow unified and uniform beings. What we say, and think, may remain coherent enough over time, but we shouldn't be fooled
by the impression that we are. If we can have an impression that our perception of a river is the actual river, and it certainly seems to be the case, I would assume we can just as easily be fooled into having the impression that our subjective experience of ourselves is really us. We take it to be some thing. I'm certainly in no doubt that all this is real, but I'm very open to the idea that I certainly don't exist as I tend to assume most of the time. "I" exists, but probably more as a collection of disparate subjective processes and events, which fortunately for me do seem to form a very cohesive collectivity with all manner of hidden connections and a very dynamic organisation. So "I" exists, and somehow knows it exists, but it's more likely that it's a different thing from one moment ago. Still, let me reassure my hardcore physicalist readers here, if any, that I'm not going loose at the joints for all my hardly-believable and suspiciously dualist subjectivist conception of reality. The physical world must somehow keep me in one piece.
EB