John Venn

Venn computing one of his famed diagrams.

John Venn (? - ?) is a crime-fighting set theorist (nonfiction).

Venn diagrams

Venn is the inventor of machines for detecting and repelling demons, now known as Venn diagrams.

Venn diagrams also show all possible logical relations between a finite collection of different sets; see Venn diagram (nonfiction).

Allies

Venn often teams up with The Sigil to find crime and solve problems in set theory (nonfiction).

John Venn / John Glenn

People sometimes confuse "John Venn" with "John Glenn".

TO DO: draw Venn diagram (nonfiction) illustration the difference.

Fiction cross-reference

• The Sigil

Nonfiction cross-reference

• John Venn (nonfiction)
• Set theory (nonfiction)