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Use of Venn Diagrams

Use of Venn Diagrams: Venn diagrams or set diagrams are specially designed diagrams that show all possible logical relations between a finite collection of sets or aggregation of things. The origin of these diagrams goes back to 1880, when John Venn invented them.

Venn diagrams are used to teach elementary set theory, as well as illustrate simple set relationships in probability, logic, statistics, linguistics and computer science.

A Venn diagram is constructed with a collection of simple closed curves drawn in a plane. According to Lewis (1918), the principle of these diagrams is that classes be represented by regions in such relation to one another that all the possible logical relations of these classes can be indicate in the same diagram.

Here is an example of how a **Venn Diagram** works.

First of all, you have think of the universe. The universe is represented by a rectangle. Let’s take ** animals** for example: moles, swans, skunks, geese, worms and horses.

This is the “Animals” universe.

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If you want to classify things according to specific criteria, such as animals being small and fury or duck billed, you need to draw two circles that shows the classification.

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Now, you have to fill in the item that corresponds to the selected criteria. Moles, rabid skunks, platypusses and the cat all correspond to the criterion.

For the other category, you need to assign the items that correspond to the criteria, i.e. duck-billed animals: swans, geese, edmontosorum and platypuses.

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There are however two items that fit in the Animal universe but do not correspond to either of the groups. Worms are small, but not furry, and horses are furry, but not small, and neither are duck-billed.

If you look carefully at the two diagrams, you will see that the platypus is listed in both circles. Therefore, the two categories should have been overlapped.

The overlapping of the two circles is called intersection. By intersecting the two, you will only have to write *platypus* once.

Venn diagrams are very useful for learners of any level. From kindergarten to college, the diagrams help people to develop their logical and linguistic train of thought.

*Use of Venn Diagrams*