Space

The idea of space has been of interest for philosophers and scientists for much of human history. The term is used somewhat differently in different fields of study, hence it is difficult to provide an uncontroversial and clear definition outside of specific defined contexts. Disagreement also exists on whether space itself can be measured or is part of the measuring system. (See Space in philosophy.) Science considers space to be a fundamental quantity (a quantity which can not be defined via other quantities because other quantities - like force and energy - are already defined via space). Thus an operational definition is used in which the procedure of measurement and the units of measurement are defined. All properties of space then follow from this definition.