In article ,
Jake wrote:

To clear up all the confusion, I offer the following copy and paste
from Wikipedia:

"Venn diagrams or set diagrams are diagrams that show all
hypothetically possible logical relations between a finite collection
of sets (aggregation of things). Venn diagrams were conceived around
1880 by John Venn. They are used to teach elementary set theory, as
well as illustrate simple set relationships in probability, logic,
statistics, linguistics and computer science (see logical
connectives)."

I think that explains things perfectly and simply and should serve to
end all further argument.

Ha, ha, very ironic! The first sentence is complete crap. They
show the 'inclusion' type relationships only.

It's a bad description, anyway. They are the overlapping circles
(or other shapes) that are often used to illustrate set membership.
The area in circle A but not in B represents the elements that
have propert A but not property B, and the area in the overlap
represents the ones that have both properties. And so on.


Regards,
Nick Maclaren.