What makes sense to me (in a speculative mode) is that there is no 'I' and no 'world' but just the signs. The 'I' and the 'world' are just two frequent signs that refer to still other signs. — macrosoft
The 'I' and the 'world' are just further signs in a grand linguistic play of signs. But pan-semiosis would be an actual model of ontology and not merely an acknowledgement of epistemic limitedness. So really, this would be two different conversations.
I like what you have been saying on Heidegger. I am in full agreement with the psychological accuracy of distinguishing between the kind of consciousness which is a biological being in the world - the enactive, embodied, ecological, etc, understanding of mind - and then the socialised, linguistic, second-order structuring of experience that comes once phenomenology is carved up by language.
Only humans have dasein of this form. And where it becomes ontologically significant could be the degree to which it takes existence in general - cosmic existence - to some kind of dialectical, end of history, extreme. We have gone beyond just words to numbers. We speak the language of pure Platonic forms.
An animal is just buried in its little world, its unwelt, in a direct, pragmatic and unthinking way. An organism entropifies. Sure it may have dasein in that there is a running modelling relation in which the world is comprehended as a (neural/experiential) system of sign. But that is a completely particular kind of relation. Task-specific and highly situational. Not at all a general one. That is why I wouldn't rush to give it ontically general significance - like talking about spirit, or soul, or consciousness, as any kind of metaphysical stuff.
But through language, humans came to socially objectify themselves as psychological subjects. That was a first detachment, a first step away from the embedded particularity of neurobiological dasein. And then through maths and logic - completely abstracted symbol play, drained of embodied semantic content to leave just a naked syntax - we have opened up the possibility of grasping something completely general about existence. We can put our hands on mathematical-strength forms or patterns. We can release the mechanistic and technological possibilities that the Universe also happened to contain as potentials.
Now humans of course make pretty pedestrian uses of what seem rather exalted capabilities. And we will probably always do so. Yet still, something new has been manifested. And it seems a key project for philosophy to make sense of that. What do we really think about machines - after we learn that they might in some proper sense stand as existence's other natural pole of being? The mechanistic and computational represents some kind of end state or limit. That would be a fact that still mostly inspires ambivalence.
To give the best example of what I mean, I am thinking about how the Standard Model of particle physics has turned out to rest on the Platonic-strength necessity of permutation symmetry. As the Cosmos developed organisation by cooling~expanding, it had to become fragmented locally by a cascade of symmetry-breakings. It had to bump down the levels of the permutational symmetries, from the most complex to the most simple.
The Big Bang started out in some very large and confused geometry. Let's call it E(8), SU(5) or SO(10), as the question is still open. But then it boiled its way down to SU(3), SU(2) and then U(1) - representing the strong force, electroweak force, and electromagnetic force.
So - as Ontic Structural Realism says - through a mathematical system of sign, a mathematical language for relating to dasein - we, as highly particular biological creatures, have come to grasp something absolutely general and necessarily true about the physical world. Reality turns out to have this hard and mechanistic formal face to it. Only these permutation symmetries are logically possible. And that is a constraint so objective that it always lay in wait as the future of any Cosmos. Chaos thought it could do what it liked. Randomness was its destiny. But permutation symmetry already spelt finitude. The ultimate shape of the future was an inevitability. The Heat Death of the Universe was foretold.
This is a bit of an excursion into the big picture. But I want to demonstrate where the relation between epistemology and ontology may lie. That question is pretty confused. And it is what Peircean semiotics makes clear, in my view.
So the big picture is Aristotelean - reality as a hylomorphic interaction of matter and form, action and constraint. possibility and necessity. Everything rests on a duality - or more properly, a dialectic or dichotomy. In the "beginning" is just a chaos of everythingness. A vagueness. And then that symmetry of fluctuations gets broken so that it becomes crisply organised into a global aspect - an informing weight of history and direction - and a local aspect, the now atomised and fragmented collection of material components or degrees of freedom, which are all the further accidents waiting to happen.
To us humans, living in the Cosmos right when it has got nearly as large and cold as it ever will be, but with still enough fuel to spark some local fires, it seems we exist in a world of reductionist construction. We live in that era of the medium-sized dry goods where matter exists stably as solids in a void. And so a mechanical or technological mode of action - the constructive mode - can have its fullest expression. Us humans are at the apex of that. Biology rests on the possibilities of constructive action, local choices. If we pick up a rock and move it, it will still be there a hundred years later most likely. Then humans have continued on along this path of constructive causality to invent machines of the most absolute kind - like computers. Mathematical machines.
But then - through the sciences of cosmology and fundamental physics - we can now grasp the particularity of the era that has informed our dasein. We have been opened up to its more general or objective mathematical-strength underpinnings. We can see the actual forms that impose a structuring necessity on "everything".
And at this point, ontology becomes semiotic. We see that the duality we are always grasping after is not the trite mind~world relation (a very particular biological dasein or umwelt), but a dualism of entropy and information (or chaos and order, matter and form, flux and logos, apeiron and peras, etc).
So semiotics deals with epistemology. At the level of biology, it become pretty clear that "mindfulness" is just about the particularity of an embedded thermodynamic relation. An organism exists with the sole cosmic purpose of breaking down entropic gradients. Dasein boils down to that. An organism's umwelt or system of signs is really something pretty physical - a collection of on/off regulatory switches.
We think of signs as marks - indelible scratches that can then become the material subject of a mindful interpretation. But really, a sign in the biologically primitive sense is a switch - a logic gate - that can be thrown. It is a bit of machinery or syntax that can be inserted into the material flow of the world so as to start to control that world with stored information.
At the level of biology, the fact that "mindfulness" is purely pragmatic is nakedly visible. An enzyme is a message from the genes to the cell. It says turn on this, switch off that. That is dasein as mechanistic action. It is all about the imposition of constraints, not some exploration of intellectual freedoms.
And when humans invented language, it too was ultimately a means of sociocultural regulation. It was the mechanistic framework which could be dropped over the top of the psychological animal to establish an appropriately detached notion of self as a social actor, keeping a close eye on the wants and impulses of the beast within.
So semiotics gives us the duality that works because it is a properly interactive one. We can see why the trick would exist. The whole of the Cosmos only exists because there is this fundamental duality between entropy and information, local material action and global formal constraint. The Big Bang couldn't have happened any other way except that it would become organised by the constraints of permutation symmetry. Confusion can't stay confused as it has to start cancelling much of itself out. Just as every baby must become organised to have the psychological truth of its embodied dasein. Regularity must emerge as habits form and enduring mechanism arises.
So there would be the story of what constitutes the particular dasein of being a conscious human. We can dissect that in the now standard psychological way to bring out the semiotic levels involved. The arc of regulating machinery from membranes and genes, to neurons and muscle fibres, to words and even numbers. On the epistemological side, this is a story of the embedded semantics dropping away and pure syntactical mechanism becoming fully realised. An enzyme is as dedicated as a lock and key. But technology is as general purpose as mathematical form permits it to be.
And then there is the story of dasein as an ontology of semiosis. The world itself arises as some kind of interaction between information and entropy ... as the most primal constructs we can apply to its description. (Of course, we never escape our epistemological situatedness to talk about the thing in itself in some naive realistic fashion. Ontology is only about the commitments we are prepared to risk our necks by. That too is already taken as read by the post-Kantian Pragmatist.)