In my family, we were rather casual about birthdays and other event days. It wasn’t unusual to celebrate a birthday, not on the exact day, but on a nearby day. We were fairly poor, so birthdays mostly consisted of a cake and a token present of some sort. (Put it this way: I can’t recall a single birthday present I ever got. We just weren’t that into birthdays.)
But I don’t recall ever not celebrating Christmas or Easter on the day. That may be as much due to my father being a pastor and having to do his thing at church on those days. The religious upbringing — and the strong streak of anti-materialism that went with it — likely accounts for downplaying birthdays and other gift-giving occasions.
Which is all to say that I missed posting on John Venn‘s birthday!
The aggravating thing is that I’ve had a folder of images set aside for over a year (I missed it last year, too). Several times this year, I’ve looked at the files in that folder to remind myself to post this post on the day. (One of these days I’ll get into the habit of posting early and setting up a delayed publish.)
Yesterday, thinking the anticipated birthday was August 14th, I checked the folder again in preparation of the putative post… only to discover the date in question was August 4th. If you heard a mysterious grinding noise in the last 24-hours, that was probably my teeth.
Considering my historical experience with birthdays, it seems somewhat apropos that this post is late. And it’s not that John Venn is some key figure for me; it’s more that he gave us something we’re all pretty familiar with and which has offered some pretty funny visual gags over the years.
If it isn’t obvious by now, John Venn gave us the wonderful Venn diagram!
Ever since, Venn’s diagram has been well-known to students of logic, math and philosophy, but in the image-based era of the interweb, it’s also become the source of some great gags. If you Go Ogle for [funny Venn diagrams] you’ll get an elephant full of results, from the droll to the sublime to the hysterical.
If you understand a Venn diagram, you understand some basic facts about sets and logic. The basic, two-circle Venn presents two sets. (Remember that a set is a maths term for ‘a bunch of things.’) A set has a membership function that determines what’s in the set. The circles in a Venn diagram are labeled to indicate that membership function.
Where the circles overlap we have a union of the sets involved — a logical AND. The overlap part is a new set that contains members of one set AND the other set. What some might not realize is that the area outside the circles is also a set: the set of things not in either of the circle sets.
This logic can be extended to more than two circles:
And gags aside, a Venn diagram can be a very succinct way to make a point. The one below sought to illustrate how the triumvirate of Kirk, Spock and McCoy spanned the gamut from highly emotional to highly logical thinking (and that neither alone is sufficient, but both are necessary).
Usually the size of the circles has no meaning. On circle set could contain thousands or millions of members while the other contains only one (or even none). The diagram only seeks to show the existence of the sets in question and present their union. The degree of overlap is also symbolic; it doesn’t actually represent the size of the union.
But you can use the size or the overlap to make a point. When I wrote about the differences between men and women, I used the diagram below to illustrate how the two sets (male and female) have almost everything in common, but that there are small areas (such as giving birth or writing your name in the snow with urine) exclusive to either sex.
I’ve also used a Venn diagram to illustrate the fallacy of the belief that success is purely a matter of trying. Luck plays a role — and as the diagram indicates — sometimes luck plays the only role (such as for those born into wealthy families).
I’ve saved my all-time favorite Venn diagram for last:
So Happy 180th (Belated) Birthday to John Venn and thanks for a great diagram!
As an aside about holidays and presents, my parents considered Santa Claus a “false idol,” so it was always clear in our household that Santa (and the Easter bunny) were definitely not real. There was never a time I believed in Santa Claus, which is why I really don’t get parents who trick their kids that way.