Saturday, April 25, 2015

V is for . . .

This month I'm posting Mad-Cool-Math Nuggets.

V is for Venn diagrams which are named for John Venn who dreamed these up around 1880. Today these pictures showing relationships between a finite number of sets are used in probability, logic, statistics, computer science, linguistics, and humor. (Wikipedia) Versatile little buggers, aren't they?

Here's your basic, 2 set model with a nonzero intersection (well, kind of):

Image courtesy: Mike Atherton

Each circle represents a set. Set A contains people who are alive. Set B contains people who are pushing up daises. The intersection (those alive and dead at the same time) contain zombies. But you knew that already.

Here is a Venn diagram with three sets. (Those of you who might take offense at irreverent humor, please skip past this image. If I could blot out the word "mindless" I would.)

Have you ever thought of the connections between popular supernatural beings in fiction and religious supernatural beings before? It's kind of interesting actually.

 Image courtesy: Frantisek Fuka

Okay, you're past the potentially offensive part. Keep in mind that sets do not have to intersect at all.

Image courtesy: Bernard Goldbach

It is also possible for one set to be entirely contained in another. Let A be the set of books you wrote. Let B be the set of bestselling books. In a perfect world, the circle represented by A would sit completely inside the circle represented by B. For those of us that are still aspiring, the intersection of A and B remains empty. Alas.


Interested in a free story with a hint of the supernatural? You can download Ghosts of a Beneficial Place through Monday for free.

I got the idea for this story from biking by a gazebo sitting next to an abandoned restaurant and thinking about how a haunting in books and movies is usually scary. The haunted place is the site of a murder or perhaps an insane asylum. Strong negative emotions stick to the place like glue. Well, could you have a beneficial haunting in a place where the emotions experienced were ones of joy? Where would that place be? How about a gazebo that held hundreds of celebrations like weddings, baby showers, and birthdays over the years?


  1. Just for once I was aware of the days subject! I didn't understand, but at least I ha heard about it. Now I almost understand it! I'm going to miss my daily tutorial when A-Z ends!
    Keith's Ramblings

  2. Idon't use Venn diagrams musch myself. They have been too often misused in meaningless managment strategy presentations.

    The 2nd example was great. Says it all. It takes more to offend me >;D

    Cold As Heaven

  3. Venn diagrams were fun to make when I was a kid. As long as they didn't get too complicated. And I just realized that Venn would make a cool character name. ;)

    That second diagram was awesome!

  4. Venn Diagrams are awesomesauce on toast. Also, John Green uses Venn diagrams in The Fault in Our Stars. It's actually super cute.

  5. I would love for the A and B book circles to be one and the same.

  6. Blot out the word mindless and that's really funny!

  7. I'm having flashbacks to elementary school because we made Venn diagrams all the time!

  8. I actually loved doing the math and filling out Venn diagrams. A lot more fun than precalc. ;)

  9. Love the example about the aspiring author (I'm in that category). The potentially offensive part - saying Jesus Christ converted mindless followers? Not potentially offensive, just offensive. My positive 'haunting' ( a bit of an oxymoron) would have to take place near water eg my favourite beach or river, or maybe in a rainforest.

    1. That's why I wanted to eliminate the word "mindless".

  10. these annoyed the heck out of me back a school but I never knew their origins

  11. I'm having a Zen moment... as I always thought Venn diagrams *had* to intersect.

    Cheers and have a wholly inclusive happy weekend :)

  12. That reminds me of a class assignment. And I can't remember... Oh, it was a math class, and they were factoring. Finding lowest common denominators. It was a very clever way of explaining it, using a Venn diagram. It was a struggle for them, though. Middle school special ed math.

  13. I want to go make a few of these diagrams now, so interesting! I always thought they had to connect at some point too.
    For me our home is full of happy hauntings, sometimes a bit unnerving but always happy to know I am not the only one that experiences them.

  14. I think you get more funny ones than serious ones these days. And I didn't know the circles could be unconnected!

    Great premise. Hauntings are usually bad news, but if someone was happy in their home and died peacefully, you can see why they'd want to hang around.

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