This paper presents the substance of the invited talk given at the 2015 Workshop on Foundations of Informatics. The idea undelying the presented research work is to borrow a plausible analogy of a \system law" from the field of Dynamics in Mechanics { the Newton's Law of Universal Gravitation. This analogy is exploited for building the law of gravitation in dynamic systems comprising a Domain of Discourse and knowledge representations (ontologies) describing this domain. As the elements of knowledge representation do not possess physical mass, this component of the gravitation law is substituted by the fitness of an ontology to the requirements of the knowledge stakeholders relevant for the described domain. It is also argued in the paper that the implementation of the developed theoretical framework is feasible as the supporting techniques, including some software tools, already exist. As the examples of the relevant component methods and tools, the paper presents the OntoElect methodology, Ontology Difference Visualizer, and Structural Difference Discovery Engine. These instruments help solve the practical problems in eliciting domain requirements, developing structural contexts for the requirements, generating the mappings between these structural contexts and the target ontology, computing increments and decrements of ontology fitness based on these mappings. It is concluded that the presented framework has prospects to be applied practically for visualization and analysis of ontology changes in dynamics. Use cases in ontology refinement and anomaly detection are suggested for validation.