Talk:Venn diagram

Maybe some explanation for the layman?

In today's New York Times there is a letter that begins:

Re “Who’s on the Family Tree? Now It’s Complicated” (front page, July 5):

Separating the trees into “genetic relatives” and “emotional relatives” might be more appropriate as a Venn diagram, since the two can overlap. A “roots and wings” tree, such as I have done, might make more sense. My children’s biological parents are their roots; as adoptive parents, my husband and I have given our children their wings to fly.

(At http://www.nytimes.com/2011/07/11/opinion/l11family.html?_r=1&scp=1&sq=venn%20diagram&st=cse)

Wouldn't it be useful for people like me, and other non-mathematic reader of the Times, to *explain* a little more in layman's language about what a Venn diagram does and why it is useful? Thanks! Hayford Peirce 03:21, 12 July 2011 (UTC)

Of course it would be useful to do that. It requires a discussion of how logical propositions can be mapped into Venn diagrams. That has not been done so far in this article. It is discussed in Venn's book Symbolic logic referred to in the article. John R. Brews 03:49, 13 July 2011 (UTC)

I added some sentences to the introductory paragraph that I hope will alleviate this problem of orientation. A section on the application of Venn diagrams would be great, or maybe a new article on design of logic circuits using Venn diagrams. For me, I'll have to wait until the urge to write such items strikes. John R. Brews 16:43, 13 July 2011 (UTC)

Thanks, John, that's exactly the sort of thing I was looking for -- and that I personally think should be in the opening paragraph of almost *every* article. Not all, perhaps, but most. And maybe even something like: "Venn diagrams are particularly useful for microbiological fusionists and deepsea fish-farmers...." Hayford Peirce 18:48, 13 July 2011 (UTC)

A practical example

PD Image
A Venn diagram illustrating sequence alignment between the genomes of three avian species

Just stumbled across this image and thought it may be useful here as a practical complement to the rather theoretical treatment of the topic so far. --Daniel Mietchen 00:16, 29 July 2011 (UTC)