# Structural and Symbolic Information in the Context of the General Theory of Information
## 2 Basic Postulates of the General Theory of Information (GTI)
_Cognitive information_** for a system \(R\), is a capacity to cause changes in the cognitive infological system \(\mathrm{IFC}(R)\) of the system \(R\). A special case of cognitive information is epistemic information, which causes changes in the system of knowledge treated as the infological system. After we outlined (defined) the concept _information_, let us consider how information exists in the physical world. **Ontological Principle O3 (the _Embodiment Principle_). ** For any portion of information \(I\), there is always a _carrier_\(C\) of this portion of information for a system \(R\). The substance \(C\) that is a carrier of the portion of information \(I\) is called the _physical_, or _material_, _carrier_ of \(I\). **Ontological Principle O4 (the _Representability Principle_). ** For any portion of information \(I\), there is always a _representation_\(Q\) of this portion of information for a system \(R\). Note that any representation of information is its carrier, but not any carrier is its representation. For instance, a text printed on a piece of paper is both carrier and representation of information, but the piece of paper where this text is written is only a carrier but a representation. **Ontological Principle O5 (the _Interaction Principle_). ** A transaction/transition/transmission of information goes on only in some interaction of the carrier \(C\) with the system \(R\). Note that interaction can be not only physical. **Ontological Principle O6 (the _Actuality Principle_). ** A system \(R\) accepts a portion of information \(I\) only if the transaction/transition/transmission causes corresponding transformations in \(R\) or in its infological system IF(\(R\)). For instance, only people with sufficiently high level of knowledge and intelligence will be able to obtain information from it when they will read this paper. **Ontological Principle O7 (the _Multiplicity Principle_). ** One and the same carrier \(C\) can contain different portions of information for one and the same system \(R\). **3. Structural Information in the Context of the General Theory of Information**  
It is possible to comprehend structural information in different ways. For instance, [PERSON] [26] treats structural information as \"the pattern of organization of matter and energy\", while [PERSON] [27] defines it as \"the way the various particles, atoms, molecules, and objects in the universe are organized and arranged\". At first, we consider the approach developed in the general theory of information. The general theory of information discerns information in the broad sense (Ontological Principle O2) and information in the strict sense (Ontological Principle O2a). Structural information is a kind of information in the strict sense being defined as a capacity to change the subsystem of knowledge in an intelligent system. It means that structural information is a kind of epistemic information, which, in turn, is a type of cognitive information (cf. Section 2). It is possible to differentiate three types of structural information. 1. Inherent structural information is information in structures. 2. Descriptive structural information is information about structures. 3. Constructive structural information is information that allows building knowledge about structures. In this section, we describe properties of descriptive structural information while inherent structural information is studied in the next section. These definitions allow obtaining key properties of structural information. Let us consider some of them. 1. Structural information can be more correct or less correct. Correctness of structural information about a system depends on correctness of knowledge produced by this information [18]. As we know, some knowledge can be more correct, better representing the essence of the system, while other knowledge is less correct, providing a worse representation of the fundamental nature of the system. Here are two examples:  
**Example 1**.