1. A conceptual expertise modeling system on a computer system having a central processing unit, a central memory and a display device working in a multi-windows graphics mode, the modeling system comprising: a plurality of windows, each window of the modeling system equipped with a system of local coordinates and with a means of marking in said each window at least one active zone capable of reacting to at least one unit of information constituted by an outside event, said active zone being associated with a group of initial editor functions that have at least one secondary reaction function; and a predefined number of conceptual objects making up a body of knowledge organized on four expertise modeling layers and displayed in said plurality of windows, each of said windows enabling the display, editing and saving of connections between ones of said conceptual objects, and each window enabling an update of the connections between the conceptual objects upon an update or change in a conceptual object, wherein the four expertise modeling layers are constituted by a strategy layer, a task layer, an inference layer, and a field layer, wherein the conceptual objects of the strategy layer are internal aims, wherein the conceptual objects of the task layer are procedures, wherein the conceptual objects of the inference layer are inference structures, operators and catalogues, wherein the conceptual objects of the field layer are concepts relations, and functions, and a first window, a second window, and a third window permit respectively the description of the functions, the relations and the concepts which belong to the field layer.