Earlier, we considered the word in general, and consciousness as a level of reflection in general. In this section, the world will be treated as a collection of individual things, interacting with each other. The words "thing", and "interaction", are used in a wide sense here, referring to any kinds of singularity, as well as to any possible way of associating one singularity with another. However, as indicated, any thing cannot exist without a material support, and there is also an ideal component linking the thing to the rest of the world. Thought both materiality and ideality are relative, there is a quite definite distinction between them on every level of the world's hierarchy, and there can be no motion without something to move, no interaction without something to interact, and no reflection without something to reflect. On the higher levels, any form life must be associated with a material body (though this body may be comprised of many organisms), and any kind of consciousness must be represented by some social body, including one or more organic bodies and a number of inorganic things involved in conscious activity.

While, on the most general level, the world is reproduced in itself via reflection, W ↔  W , on the level of singularity this returning of the world to itself appears as interaction of distinct things: X ↔ X' . It should be noted that every connection of things in the world is bi-directional: speaking of relation, action, or information, we always mean mutual relatedness, interaction, communication. In the simplest case, the links X → X' and X' → X are of the same kind; we say that such links belong to the same level of hierarchy. For example, in classical mechanics, two material bodies act on each other with equal force, but in opposite directions; consider also a chemical bond, symbiosis, a sexual intercourse, a political treaty or a contract. However, it often happens that, for some link X → X', there is no inverse link of the same level; this does not mean that there is no inverse link at all, since link do not need to be immediate and direct. Things may be linked to each other through another thing, a mediator: X' → M → X. While both links X' → M and M → X may be of the same level, the resulting indirect link X' ⇒ X no longer belongs to that level, and it may be as well mediated by a different mediator: X' → M' → X. The double arrow ⇒ here denotes the unity of all the possible paths from X' to X, including those with multiple mediations; transition from the collection of mediated links to such a virtual link will be referred to as lift-up of mediation.

The difference between direct and virtual links is similar to the difference between the material and the ideal. And, like the opposition of the material and the ideal is relative, the distinction of direct and virtual links depends on the level of hierarchy.

Mediated links are fundamental in the sense that any other kinds of indirect links can be reduced to them. For instance, one can consider collateral links:

or

That is, presence of direct links X → M and X' → M implies that there is a link X ↔ X' , and simultaneous links M → X and M → X' also imply that X « X' . Collateral links are different from direct links, as well as from mediated links. However, noting that X' → M implies a virtual link M ⇒ X' , we have a higher level mediation X → M ⇒ X' , and hence a virtual link X ⇒ X' . Similarly, lift-up of mediation in X' → M ⇒ X gives X' ⇒ X . The combination of these two virtual links results in the collateral link. As a side result, we conclude that collateral links are not necessarily symmetrical, since they involve different mediated links.

The inverse logic is also valid. If there is a virtual link X ⇒ X', there must be some kind of mediation that is characteristic of this very virtual link; moreover, there must be a special kind of mediator M(X, X'), linking X to X' in the most straightforward way: X → M(X, X') → X'. In other words, M(X, X') represents the link ⇒, or implements it. Due to relative distinction between direct and virtual links, one can conclude that any link at all is represented by a definite object, or implemented in a definite way. Obviously, implementation does not need to be unique, and the same link can be unfolded differently.

It should be noted that any connection in bilateral in the real world, and the links may be mediated the both ways, producing a mediated cycle:

Evidently, both M and M' can be considered as mediating the connection between X and X', as well as X and X' can be considered as mediating the connections of M and M'. In principal, nothing makes one choice more preferable than another. Still, in most cases there exist "dedicated" mediators, which are more suited to serve as the representatives of interaction, signals; on a higher level, such signals may be represented by material things embodying the lower-level interactions. For example, in physics, bodies may be considered as directly interacting (e.g. Coulomb interaction of atomic electrons), or interacting via a field (electromagnetic or other), which is an obvious example of mediated interaction. However, in quantum physics, fields are always associated with particles (the carriers of the corresponding interaction), and the difference between gauge fields (those associated with common interactions) and ordinary "material" fields may become diffused.

The mediators M and M' may either be of the same kind (like electromagnetic field mediating the interaction of charged particles), or the direct and inverse processes may be mediated differently (like in catalytic reactions in chemistry, or biological cycles). In the first case, all interactions can be considered as occurring within the same level of hierarchy. The second case also allows such "planar" consideration, but there is yet another option. Thus, if the mediators M and M' are qualitatively different, we could treat one of them (say, M) as belonging to the same level as X and X', while the second mediator would be put "outside" the system X → M → X' , providing a kind of environment for it:

Such a representation implies that X and X' are, in a sense, "closer" to M than to M' ; for physical interactions, there is a difference in the characteristic times of the corresponding transitions. Such a distinction is related to distinguishing the levels of mediation by the degree of their indirectness. However, due to relativity of the latter distinction, one could expect that separating a system from its environment may be a non-trivial task.

Discussion of the hierarchy of links is not as abstract as it may seem. Thus, formation of associations in animal and human psychology provides a vast area of application for hierarchical approach. Each association forms on the basis of certain material processes, and is governed by external conditioning. However, once association (virtual link) has formed, it becomes represented by certain environmental changes, which support reproduction of particular mediations. The existence of a characteristic mediator for every link is of crucial importance for understanding consciousness. One can conjecture that virtual links have to do with consciousness itself, while the corresponding characteristic mediators are readily associated with conscious beings. However, not any virtual link can be related to consciousness, and one comes to considering the hierarchy of mediators.

Though there may be many dimensions of unfolding this hierarchy, the universality of mediation seems to be the most appropriate for outlining the area of reason. One could observe that different types of mediation dominate on the levels of existence, life and activity, as introduced above. Thus, the inanimate world knows only passive mediation: coexistence, intermediate states of motion, correlation, etc. Mediated interaction is one of the most important cases. In the chain X → M → X' , the signal M is emitted by X and absorbed by X'; in many cases, X and X' continue to exist as they were, with only their state of motion changed. The mediators are usually of the same kind as the things connected, and they behave like particles, waves etc. Some inanimate things seem to be unable to interact via certain interactions (for example, strong interaction of leptons is forbidden). However, in general, any inanimate thing can interact with any other thing, and hence mediate interactions of other things. Such mediated connections between inanimate things are random, in the sense that they are not necessary for the existence of the things themselves. For instance, an isolated electron will still remain an electron, and a molecule does not need to interact with other molecules to become a molecule of that very sort. Interaction is not needed to support the existence of inanimate things, and often leads to their destruction, or transformation into other things.

The animate nature is characterized by active mediation, with the mediator M consuming the thing X and producing the thing X'. Unlike the interacting inanimate things, X does not exist any more after it has been consumed, and X' did not exist before it has been produced by M. On this level, M is not merely effectuating the interaction between X and X' — now it is seeking for X to produce X'. Moreover, the very existence of a living thing (an organism) depends on its ways of consumption and production, and terminated metabolism means death. This is the level of necessary mediation. On this level, mediations become essentially asymmetrical: the processes within an organism are often clearly distinct from its interaction with the environment. However, this does not mean that the organism can be defined on itself, isolated from its connectedness to other organisms and the inanimate world. On the contrary, an animal is essentially a representative of its species, and a part of an ecosystem; if a group of animals becomes isolated from their natural habitat for a long time, this results in either their degradation and death, or transforming into another species adapted to the new environment.

Like inanimate things can be joined by mutual interactions into a composite body, organisms tend to cling together forming a higher-level organism. However, such coexistence is much more restrictive, since any one of the organisms living together requires a quite definite environment to live. In every particular synergy of different organisms, the members of this communion have to adjust their structure and behavior, to serve the whole. Thus, the organs of the animal body, while remaining relatively independent organisms, are functionally dependent on each other, and evolve to the forms, which cannot live outside the body; compare this with the molecules in a solid body: while slightly changing in the solid body's structure, they can always be separated from it, and still continue to exist. There are other examples of hierarchical organisms, uniting and transforming lower-level organisms: a cell as a system of organelles, an organ as a community of cells, a colony of insects as a collective organism, a biocenosis, a biosphere in general...

The relation of the living organism M to the things X and X' connected through it is relatively rigid, pre- defined, characteristic of the species. It is only in higher animals that more flexible types of behavior become possible, and X is not necessarily consumed to produce X', and different ways of consumption are possible to produce the same thing. In particular, some organism of the same species can serve as a trigger for certain organic processes, while not being directly involved in them ? in a sense, this resembles catalytic reactions in chemistry. The mechanism of such communication between higher organisms is still based on innate metabolism, with one animal producing some thing that is consumed by another, which leads to behavioral changes; however, this kind of consumption is not immediately related to the basic metabolism that supports the animal's life. In other words, the behavior of the organism is hierarchical, involving both the level of vital functions and the level of conditional functions supporting the organism's ability to maintain its basic metabolism, and life. In higher animals, the supporting functions significantly overweigh the basic metabolism, which is a premise of consciousness formation.

It is only on the level of subjectivity that the mediation becomes really universal, so that any two things can be linked through the mediator of a new type, the subject. This universality of mediation differs from random mediation on the inanimate level, since it is necessary for the subject, and any subject is bound to bring things together, to remain a subject. However, this also differs from organic mediation, since it is no more restricted to a specific class of links, extending to the whole Universe. Such an all-embracing necessity is called freedom.

While inanimate mediators only link things in their immediate environment, and living creatures can effectuate only those transformations that are compatible with their physiology, the subject can link anything to anything, with no physical or physiological limitations. Things that do not directly interact, to any appreciable extent, become united in the activity of the subject, thus restoring the unity of the world. For instance, there is no physical reason for the Polar star to influence the movement of a ship — and no physiological reason for the human organism to react on the starry sky in any definite way — however, the course of the ship may be corrected through the observation of the stars by a conscious being. The subject can even link things in time, not only in space: events separated by billions of years become related in consciousness. But the most important consequence of the universality of subjective mediation is the subject's ability to link not only material things but also any aspects of their existence, abstracted from the things themselves. Relations between things are linked to things, or other relations, and there is no limit to the complexity of abstract mediations. The subject is the only way to establish such links, and it is for this universal mediation that consciousness appears in the world.

As universal mediation, the subject can mediate any relations between subjects, including the subject's relations to itself. This representedness of the subject's activity in the subject is what we call consciousness.

It should be stressed that the subject cannot be reduced to mere thing, or an organism. Both inanimate things and living things are necessary to represent a subject. Specifically, consciousness cannot be a mere property of the human body, or any part of it. And, of course, there is a hierarchy of subjects: any group of subjects can form a higher level subject, and there is much more diversity than in biological communities.

While any thing becomes linked by the subject to any other thing, the subject primarily links it to itself: X → S → X . In other words, once the thing has been assimilated by the subject, it will contain the subject in it, thus becoming an object. That is, an object is anything at all in its relation to the subject. For the subject, the world unfolds itself as a hierarchy of objects, nature.

This means that the subject mostly mediates the relations between objects, rather than mere things or their properties, and the mediation scheme takes could be rewritten as O → S → O' . On the most general level, the subject appears to be the universal way of nature's self-reproduction; this universal reflectivity of nature is called spirit.

It should be stressed, that the subject is an object too, and hence a part of nature. However, this a very special kind of object, namely, performing the universal mediation. The things and organisms implementing the subject do not need to be representatives of the subject in every respect, and they retain their existence as material things, or living creatures. The subject should not be identified with its implementation, and no finite implementation can represent subjectivity in full. For instance, when any human combines being a material thing with being a representative of a biological species, and, in certain respects, the subject of conscious activity.

Now, we have the triad of mediator types:

a thing → an organism → a subject ,

corresponding to the hierarchy of universality:

randomness → necessity → freedom .

Of course, any hierarchical structure is relative, and the living creatures could not have existed if there were nothing in the inanimate world that would be akin to life; similarly subjectivity has its origin in life, and reflected in it. Within the random mediation characteristic of the level of existence, there may be a hierarchy of specific forms, differing in their universality. For instance, sequencing in atomic and chemical reactions could be considered as a germ of life. On the level of consciousness, there is a hierarchy of its manifestations, some of which resemble animal, or even inanimate reflection. It is only in a specific context that the attribution of a certain type of behavior to consciousness may have sense.