A measure of a body’s or system’s ability or capacity to do work, and like work itself it is measured in joules. There are various forms of energy that can be converted one into the other by suitable means: chemical, electrical, heat, kinetic, nuclear, potential and nuclear energy. Conversion of these forms can only occur in the presence of matter. This well-defined measure in physics has been carried into cognitive psychology as a metaphor for ‘mental energetics’, with all the loss of original meaning that this sort of border crossing incurs.
See Central pattern generator (CPG), Closed system, Cytoplasm, Joule, Kinetic energy, Matter, Maximum aerobic power, Newtonian (or classical) mechanics, Oligosaccharides, Open system, Work