摘要: This paper presents a methodology for extending representation and reasoning in Qualitative Physics. is presently used various applications. The qualitative modeling of physical system weakened by the lack quantitative information. may lead analysis to ambiguity. One aims this cope with main idea reproduce physicist's ability evaluate influence different phenomena according their relative order magnitude use information distinguish among radically ways which behave. A formal system, FOG, described represent structure kind apparently vague intuitive knowledge so that it can be reasoning. validity FOG an interpretation mathematical theory called Non-Standard Analysis then proven. Last, shown how structures quantity-space.