"Kelvin... formed... the view that... the essential component of the steam engine is the cold sink—the surroundings into which waste heat is discarded. The crucial part of the engine... didn't have to be designed or constructed... inverting common sense. ...Kelvin's conceptual somersault led him to promote ...the central ...cold sink to a universal principle ...all viable engines have a cold sink ...not ...[in] those words but ...[in] essence ...Take away the cold sink and the engine stops ..."