The notion of objectivity or absolute truth implies that there is some way the world really is, apart from anyone's actual perceiving of it. This, presumably, was the countenance of the world before there were any observers to observe it. What happens, when the observer tries to give shape in imagination to this unimaginable countenance, is that one's actual experience is mistaken for the world-in-itself. It may seem quite reasonable to think that the universe is simply the way it looks to us, and that (apart from its dynamic evolution in time) it appeared much the same before the arising of life and conscious observers. But there is a subtle error involved in this assumption. We need only ask: appeared to whom? What does it mean, in other words, for there to be an object without any possible subject, or whose appearance is universally the same to any subject? This question cannot arise for the pre-subjective mind, but as conscious subjects we are stuck with it. It's the quandary of Berkeley's famous "If a tree falls in the forest..." We will refer to it here as the problem of cognitive domains, because it involves mistaking the domain of one's experience for some other domain of objective truth.
A mind has only the relative and subjective realm of its thought and experience in which to speculate about possible other realms such as an objective world or an absolute truth. It is likely to paint its picture of the latter in terms of the former:
"Mortals suppose that the gods are born and have clothes and voices and shapes like their own. But if oxen, horses and lions had hands or could paint with their hands and fashion works as men do, horses would paint horselike images of gods and oxen oxlike ones, and each would fashion bodies like their own."
In other words, we can imagine the territory only as it is portrayed to us in our map. Unwittingly, and circularly, we take this image on the map to be the territory which the map portrays.
From the point of view of the subject, a cognitive domain is the range of experience of a mind-- all that is "expressible", so to speak, in the system of that mind. In terms of behavioral description (of the object), it is the range of discriminations an organism can make.
Every creature has its cognitive domain whether or not we think of it as having conscious experience, for all creatures make discriminations. Many rely on sense modes radically different from the familiar five senses. To mention only a few, these include sensitivities to water pressure (depth), polarization of light, infrared and ultra-violet light, magnetic fields, etc. Each sense modality also defines a separate cognitive domain. The visual appearance of a wound to one's body is in a different domain from the felt experience of pain associated with it. A distinct level of processing within the nervous system may also be considered a cognitive domain. These considerations would apply to an artificial system as well.
As an open system, an organism is immersed in an environment with which it exchanges information as well as energy. This is the situation as described by a human observer. It may be that the organism has no abstract concept of its environment in the sense that we do, let alone concepts of information and energy. It may appear to us that the organism perceives and acts upon the environment perceived by humans, while its representation of this environment is limited by its cognitive domain. But this is highly anthropocentric. Moreover, the whole situation can be viewed quite differently. A nervous system can be regarded as a completely closed loop.  Changes on the sensory surfaces initiate activity in the brain which (from an observer's point of view) results in some action on the environment. But this action can be regarded as taking place exclusively upon the sensory surfaces, since its effect is to bring about changes in them which the creature holds to be desirable. In this way, all that the organism is ever dealing with are transformations of its sensory surfaces. Its goal is to maintain the latter within certain limits, just as the homunculus within the giant head maintains his instrument readings. The very idea of an environment is an intrusion from a human cognitive domain. The irony of this solipsistic analysis, of course, is that the human observer making it is in the very same position. He too is an organism engaged in maintaining constant a set of internal conditions, and all his theories are but a part of this process of self-regulation!
While conscious experience is the culmination of elaborate processes, which themselves remain outside awareness, every stage in a flow of information processing may be considered a distinct domain. Each domain, in other words, is the subject of propositional knowledge about the presence of certain entities. Out of this knowledge is assembled a new domain, which can in turn be searched for higher entities. This bears on a long-standing debate in cognitive science concerning the role of images (and therefore of consciousness) in the forms of representation used by cognitive systems. A representation is a mapping from one domain to another. It may be propositional in the way that a book, which consists of statements, maps or represents the subject it covers. An image seems rather an analogue, but can be understood in propositional or digital terms. Whether or not a particular point on a television screen is illuminated constitutes a proposition, and from the ensemble of such digital events a global analog representation emerges that embodies the accumulated propositional knowledge of prior stages of information processing. We must bear in mind that it is the human brain that constructs the cognitive domain of the image from the domain of scintillating picture points. (The pattern of dots may mean very little, or something different, to a cat or a moth, or even to a human who has never before seen a television, or one experiencing an altered state.) The mind may then search the domain of the image for propositions in yet higher domains of meaning-- esthetics, heroes, plots, etc. Each level is part of a hierarchy of constructed domains. Analog and propositional are terms relative to the level or domain in question. They are not mutually opposed, but have a dialectical relationship in the hierarchies of the nervous system. An image is a domain defined by a set of propositional operations. Further propositional operations may be performed upon it.
A language one fluently understands is a different domain than the collection of sounds ones hears as gibberish before learning the language. Similarly, the babble of the senses, before it has been processed in the nervous system, is not the same domain as the sensory experience which results from that processing. Confusion arises around the idea that we can have some access in awareness to stages of sensory processing prior to the end product which we experience. The hypothetical notion of sense data was invoked by Locke and later philosophers as a kind of pseudo-object in the Cartesian style. Sense data, presumably, are what we would experience if we could experience the domains of sensory input and other pre-processing stages of perception. In fact, the nervous system is not designed so that "we" have conscious access to these levels. One is, however, able to exercise special attitudes toward what is perceived. Every painter, for instance, knows how to "flatten" visual space and see objects, not as three-dimensional things, but as shapes and areas of color bounded by lines. We fancy that such objects of introspection bear some resemblance to lower domains of sensory processing, but they constitute in fact a higher domain as subjective artifacts of conscious attention.
The world has survived the comings and goings of generations of observers. It seems to persist during one's inattention or sleep. It must have existed before we were born and even before the arising of life. It is reasonable to think that it will continue to exist after one's personal death and after the passing of all life from the earth. While the existence of the universe may not depend on us as observers, certainly our knowledge of it does. The universe we know is a product of our own mental activity in a specifically human cognitive domain. It is this knowledge we mistake for the universe itself. But surely something must exist "out there", in its own right and not just as the experience of some creature. If cognition is a map, surely there is a territory! The problem is how exactly to conceive it. Experience is the product of the map, and the territory can only be known through experience-- through the map. Every perception or conception concerning the territory is part of the map. The territory itself is unknowable, since knowing is by definition the map-making activity of a cognitive agent.
The subjectively conscious mind can grasp that it constructs experience of the world as a representation in a cognitive domain. It can understand that its experience is not the world-in-itself, just as a film of a real scene is not the scene itself, but constitutes a separate domain. It can imagine the scene unfilmed, but cannot picture the world-in-itself unpictured. As though at once film-maker and audience, we are eternally confined to watching our own documentary on the the world outside. When the show is over and the lights go on, we discover that what we are presently witnessing is also a movie, a story nesting the previous story. We are trapped in the domain of film! In the same way, the proposition that there exists a reality untouched by mind is itself but a mind's assertion. Any notion of an absolute world, outside all cognitive domains, is nonetheless an idea in a cognitive domain. This is why the good Bishop Berkeley kept God around to hear the trees that no one else heard falling in the forest: to exist is to be perceived by a mind (or so he said). The raw fact of mind-- of being a cognitive organism-- is that we experience all within a finite cognitive domain. The specific achievement of being human is to have a highly flexible and relatively objective cognitive domain, with some conscious control over our point of view. But how can we pretend to have no point of view at all?
Concerned about the difficulty of explaining experience in terms of physical cause, a contemporary philosopher writes:
"If physicalism is to be defended, the phenomenological features must themselves be given a physical account. But when we examine their subjective character it seems that such a result is impossible. The reason is that every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view".
But it cannot abandon all point of view. An individual subject is absolutely unique if only because no other observer can share precisely his point of view in space-time. The observer in physics is an idealized standard based on the relative interchangeability of subjects, but the point of view of the observer is nevertheless a point of view. What makes the standard possible is the agreement precisely not to consider "subjective" aspects of experience in the field of discussion. What does this actually mean? It means not applying the subjective frame to one's own experience of observing, as well as eliminating measures which cannot be quantified, repeated, etc. It would be irrelevant for an observer to record her personal experience of observing-- unless it qualified the reliability of the observation-- for the physical world is the field of discussion, not the experience of the observer. But this does not mean that the observation could be made without personal conscious experience-- by an unconscious observer or by a machine. Perhaps some observations are so routine that they can be made as "automatically" as one drives a car. Many are recorded by instruments. Nevertheless the significance of the measurement must be considered at some point if it is meaningfully held to be an "observation" at all. At some point consciousness enters.
Points of view, particularly ones that pretend to objectivity, are usually identified with the visual sense. More than the other senses, vision lends itself to a confusion of cognitive domains. It is easy enough to think that the quality of pain does not exist "in itself", but only as a judgment made by a nervous system. It is much harder to grasp that the same reasoning must apply to visual "appearances"-- leading to the conclusion that the quality of a visual appearance has no more objective existence, outside a nervous system, than that of a pain. Classical science attempted to eliminate all subjective qualities-- such as feelings-- from its descriptions, in theory leaving only properties accessible to any observer, regardless of subjective state. (Implicitly, this means any human observer trained in the methodology of western science). Vision is paramount for reasons related to its quantifying and objectifying capacities, which make consensus relatively possible. In most instances we can discriminate with more precision visually than with other senses, which facilitates agreement about measurement. But structures in the world indicated through visual perception must be distinguished from visual qualities (such as the color blue), while we must understand that the experience of color is itself an appreciation of a structure in the world-- namely, the fine structure or frequency of light.
The ideal of science, modelled on the objectifying quality of vision, has been to describe the world as a realm beyond the limits of the senses. And instrumentation has vastly extended these limits. The ancient Greek thinkers, and their Renaissance admirers, sought to distill out of the flux of phenomena the unalterable real aspects of matter. They set about to create a theoretical domain transcending sensory experience, yet this conceptual realm was in fact based on the visual sense.
Scientific or objective description is supposed to take place from a "third-person" point of view. Yet all description is necessarily in the first person: from the point of view of "I". So-called objective description, which leaves out mention of the observer's experience or excludes conscious states of the observed organism, merely fails to acknowledge the consciousness of the observer. What is meant by "third person" is simply that the observer is talking about the external world, not about his personal experience. It cannot be pretended, however, that the observer has some way of knowing about the external world other than through personal experience.
All observers stand in a first-person epistemic relation to the world-- either through the instrumentation of the observer's own body or through some external device which extends the agency and the epistemic relationship of the observer. The fact that I can estimate the frequency of light either through my sensory experience or with a spectrometer does not place these measures on a different epistemic footing. The spectrometer may isolate frequency better, and measure it more precisely, than human vision. But the idea that the measuring system is objective, because it has no subjective viewpoint of its own, is absurd since it is not the device which is making the measurement but the observer.
First and third person accounts are distinct domains of description. Though temperature and pressure are subjective first-person experiences, they are also macro properties of molecules which may be "objectively" described in third-person language. But what does this actually entail? It means that the conscious subject as observer notes the reading on some instrument that is not the observer's body-- e.g. a thermometer or pressure gauge. This reading is held to correlate with an objective property of the matter in question (e.g. a gas). To experience this same property "directly" or "subjectively" means to measure its effects using one's own sensory organs as instruments. Another way to put this is that felt temperature and pressure are experiences of "what it is like to be" the instrument which is the observer's body.
Third-person observation isolates a system by separating the system-to-be-observed from the system-which-is-observing. If we try to expand the account to include the latter, we simply redraw the line somewhere else, redefining the observer who is still excluded. So on in an infinite regress! The deep truth revealed here is that the subject can never be phenomenal object. The problem of consciousness (if there is a problem) is not resolved through third-person description, but only deferred by transferring consciousness from the system observed to an observer supposedly outside the system.
Nevertheless, the scientific picture-- at least as portrayed in popular accounts-- pretends to depict what the object looks like before it looks like anything at all: the naked object, the unmade-up face of the world. In favor of the ideal of objectivity science rejects the cognitive domain of ordinary (first-person) experience as merely a cognitive domain, only to construct new cognitive domains that it does not acknowledge as such. Implicitly it holds its entities-- no longer perceived but conceived-- to be the building blocks of the objective world-in-itself, while these conceptions often remain tied to acts of visual imagination. Though the validity of scientific models may depend strictly on their mathematical power of prediction, their intuitive appeal refers back to ordinary (subjective) experience, cloaked as objective constructs.
Cognitive science implicitly adopts the domain of physical description-- the world portrayed by physics-- as the causal substratum of the phenomena it researches. This gives rise to some confusion concerning the nature of the fields in which mind grazes. Merely to explain that the brain organizes its picture of the world, based on its contact with the world it pictures, is too vague and obviously circular to be satisfying. Scientists therefore have recourse to entities, held to be more fundamental than the objects of ordinary perception, as the starting points for causal explanation of cognitive processes. But it is only a convenient manner of speaking. One is never aware, in any sense, of one's own nerve impulses, or of the photons or molecules which trigger them, nor of any other such theoretical constructs in the domain of science. We are simply aware of the world as presented in our normal cognitive domain, which includes the objects encountered in daily life, but not the microscopic events of physics or neurology. To begin with the world of physics as the point of departure for explanations of mental activity must be done with circumspection. For the whole biological enterprise of cognition leads up to and includes the physicist's constructed version of reality, which is then recycled as the starting point! Schopenhauer likened this bootstrap operation to the Baron von Munchausen who-- in order to cross the river without drowning-- lifted himself and his horse above the water by pulling up on his own hair! The ordinary human cognitive domain cannot logically serve as the raw material out of which to construct the ordinary human cognitive domain.
The Mind-Body Problem is, above all, a problem of cognitive domains. The mental appears as a subjective domain, somehow caused by the objective physical one, while the latter appears simply to be the world, rather than an appearance in human consciousness. The objective physical world, by definition, is held to be a domain existing independently of the perceiving or knowing mind. But the subjective domain of experience is not caused by neural processes. Rather "experience" and "neural process" are descriptions in distinct cognitive domains of the same event.
Consider the two cognitive domains of sight and sound. The sight of a starting pistol going off in the distance with a puff of smoke, and hearing the sound of the shot an instant later, are two experiences registering the same occurrence in the world in two cognitive domains. One is not held to cause the other, neither is considered an "epiphenomenon" of the other, and there is no philosophical problem with their relationship. This does not stop philosophers from claiming that the sight and the sound as subjective experiences are both epiphenomena of objective neural processes or are caused by them.  The fact that the relationship between physical processes and experience is held to be problematic is the Mind-Body Problem. However, the subjective is not an epiphenomenon of the objective. Rather, the two are experiences of the same thing in different cognitive domains.
Certainly experience is a correlate of brain process, because the latter is a transform of events in the world which cause the brain process and to which the experience refers. For this reason, my experience of the pistol shot contains the same information as that registered in someone else's cognitive domain who could happen to be observing my brain process at the time of that event. (Unless I could attend to the two experiences simultaneously, this observer could not be me, for what would then be the referent of my experience would not be the pistol shot but some visual experience of seeing my brain or some thought about various measurements).
It makes sense to say that brain processes cause behavior but not experience, because 'brain process' and 'behavior' are elements in the same cognitive domain-- that of the observer, whether it be myself or someone else. The cognitive domain of first-person experience is distinct from that of the observer, both in content and in logical level, even when both observer and subject happen to be the same. (In that case, one is observing oneself observing oneself observing oneself... ad infinitum. Nevertheless, in this hall of mirrors, each instance of "observing myself" is on a different logical level, defining a distinct cognitive domain).
"Qualia", "sense-data", "phenomenal appearance", "raw feels", etc., are objects of observation when experience is bracketed as such, defining a cognitive domain distinct from that of the world. The cognitive domain of my first-person experience of the pistol shot as an event in the world is distinct from that of my bracketed experience of the pistol shot as an element of a private inner subjective show. If there were but one cognitive domain in question-- that of events in the world-- there would be no problem. There would only be the pistol shot going off-- period! One could extend the description of events in the world to include a causal description of the effects upon my body's sensory system, its startled flinching and minute chemical and physiological changes. Nowhere in this description would anything be bracketed as "experience". Alas, this would be the scientific dream of objectivity come true, if it were the case! But even to speak of "events in the world" (as opposed to what?) already subtly presupposes subjective awareness.
The specific quality of experience in a particular sense modality-- what visual experience is like as opposed to, say, what auditory experience is like-- is not knowledge of the world but of the workings of that sense modality. There may be something which can be learned about the world through vision that cannot be learned through hearing, but it is not the flavour, so to speak, of visual experience. Rather, knowledge of what seeing is like is knowledge "by acquaintance" of human vision and, more generally, of what it is like to be a conscious human subject.
Objective knowledge of the world is abstracted from knowledge by acquaintance. It refers to facts about the phenomenal world but not, in a sense, to the phenomenal world itself. It is knowledge of structure, which means differences of qualia, but does not refer to that which the differences are are of. Such knowledge is objective in the sense that it is invariant per standard human observer. This is analogous to the situation in dynamics, where the observer cannot know absolute velocities but only the relative difference between his velocity and that of another object or observer. I cannot know your experience of the color red, nor you mine, but we can both be aware of differences between two shades of red and communicate about them. The perception of such differences is what we mean by objective knowledge or information. Since by definition it excludes sensory qualities, we should not complain that it is deprived of them, or be troubled to explain how the domain of subjective experience (that is, of sensory qualities) arises from domains of information or other such constructs. On the contrary, if all perception is perception of difference, then the experience of color (and of any qualia) is itself a perception of differences, not among qualia, but in the objective world. The experience of a given color must then be a perception of the fine structure of light, just as the experience of tone is a perception of the fine structure of sound. The Problem of Cognitive Domains is that an objective domain is conceptually abstracted from the domain of experience, and then an attempt is made to derive the latter from the former. Owing to the fact that these domains are not on the same logical level, there is an inevitable "explanatory gap". We want to understand how conscious experience can arise through physical processes in the world, while both "conscious experience" and "physical process" are categories on a different footing than each other or than the unselfconscious awareness in which the world simply is. It is as naive to hold that the world-in-itself is the reality given in concepts of physical science as it is to believe that it is the reality given in everyday experience. While both scientific concepts and everyday experience refer to structures in the world (i.e. differences), both also "fill in" such information with the qualities of experience or imagination. We do not see blue light and think "this is a structure of such and such frequency". Rather the experience of blue is the perception of that structure. Similarly, the concepts of wave and particle refer to structures in the world, yet are imaginative extensions of experience in our ordinary cognitive domain. Perhaps this is the reason for the increasing mathematization of physics. Mathematics alone is free of "quality". Knowledge of the world-in-itself ultimately can only be mathematical.
The error at the core of the Mind-Body Problem is that the world of physics is mistaken for the world-in-itself, as the initial condition in an explanation of how "experience" arises from "material processes"-- or how qualities arise from seemingly denatured information about structure. Yet material processes are only known through experience, and qualities are a perception of structure.
The Problem of Cognitive Domains is the fact that we are not content, like the ancient Taoists, to let the world-in-itself be ineffable, unnamed. But either it is transcendent and unknowable in experience, in which case it cannot be what is given in our ordinary cognitive domain (nor in any other cognitive domain than that of mathematics). Or else it is knowable in some cognitive domain, and so is not independent of mind. In the "equation of experience", there is no isolated access to the variable of the world-in-itself, because "accessing" is an action of the other variable, mind.