Nested Venn Diagrams

Nesting is used to extend Venn Diagrams from their usual practical limit of three or four sets to a form that readily handles five to eight sets. Although devised independently, such nested diagrams can be viewed as the application to Venn Diagrams of an idea proposed in 1896 by Lewis Carroll, in the context of his alternative set diagrams. Such nesting is rarely if ever used today, but has genuine practical value; ironically, it appears to be more useful in the context of the familar Venn Diagram than when applied to Lewis Carroll’s own, less popular, diagrams.