Tried at first, as others have done, to represent the complicated propositions by the old plan but the representations failed altogether to answer the desired purpose and after some consideration hit upon the plan here described (Venn 1880c, p. Hence, we simply shade the compartment x non- y to obtain the diagram of the proposition, shown in Fig. The proposition asserts that the class x non- y is empty. Hence, we need a two-term diagram where the four combinations xy, x non- y, non- xy and non- x non- y are represented, as shown in Fig. Let us consider the proposition ‘No x is y’. For instance, shading a compartment expresses its emptiness. Then, one adds syntactic signs on this general framework to indicate the state of the compartments. First, one draws a primary diagram that represents the combinations between the terms involved in a proposition or an argument. This method of representation consists in a two-step procedure. It is well known that John Venn first published his celebrated logic diagrams in 1880 (Venn 1880c). Therefore, the question of how Venn diagrams originated in the first place has been around for a long time. In fact, Euler diagrams are much older than Venn diagrams, and there are also numerous Euler diagrams that cannot be Venn diagrams. However, research since the 1990s has shown that both diagram systems have their own syntax and semantics (Shin 1994). Venn diagrams and Euler diagrams are often mentioned in the same breath: Since both diagram systems are mostly formed by using circles, appear intuitively understandable at first glance, and in some cases even look similar, this confusion is not surprising. Like many other types of diagrams, Venn diagrams not only have the property of presenting information clearly, but in the best case they can also generate new information than was not intended when the diagram was created (Shimojima 1996). Venn diagrams belong to the group of logic diagrams in the field of visual representation and reasoning (Moktefi and Shin 2012). Together with Euler diagrams, tree diagrams, squares of opposition etc.

They are used to represent relations between entities, concepts, classes, or more generally to present information. Venn diagrams are nowadays used not only in logic, but in almost all areas of science, for example in biology, translation science or artificial intelligence (Edwards 2004 Meulen 1990 Nakatsu 2009).

Different venn diagrams