Changes

|Description=At any moment of the history of science, there are certain ''theories'' that the scientific community of the time accepts as the best available descriptions of their respective domains. According to the original definition of the term suggested in [[Barseghyan (2015)|''The Laws of Scientific Change'']], the class of ''theory'' includes only those propositions which attempt to describe a certain object under study. [[CiteRef::Barseghyan (2015)|pp. 3-5]] A theory may refer to any set of propositions that attempt to describe something. Theories may be empirical (e.g. theories in natural or social science) or formal (e.g. logic, mathematics). Theories may be of different levels of complexity and elaboration, for they may consist of hundreds of systematically linked propositions, or of a few loosely connected propositions. They may or may not be axiomatized, formalized, or mathematized. It encompasses all proposition which attempt to tell us how things were, are or will be, i.e. substantive propositions of empirical and formal sciences. The definition excludes [[Normative Theory|normative propositions]], such as those of methodology, ethics, or aesthetics. [[CiteRef::Barseghyan (2015)|pp. 3-5]] Examples of theories satisfying the definition include the theory that the Earth is round, Newton's laws of universal gravitation, The phlogiston theory of combustion, quantum mechanics, Einstein's theory of relativity, and the theory of evolution.