The concepts from figure 1 are defined in table 2-1 below.

From these, other concepts can be explained and defined, in particular for those who are first learning a language.

Each concept and all their attributes are defined in natural language words.

The following example may help to clarify some of the concepts defined above.

The concept of a European citizen must certainly be defined.

It is very important that the concept of family should also be defined effectively in this field.

It seems to me that the concept of commerce has not yet been clearly defined.

An individual concept is then defined as a function of individuals in different possible worlds.

This concept of liability was not defined clearly enough in our legislation.

While widely discussed, the concept of a G-2 has not been fully defined.