November 4th and

Not too many people concern themselves with the “Death Date Paradox.”

This would be the evil twin of the widely known “Birth Date Paradox” or "The Birthday Problem" - that mind-wrenching mass of mathematics and statistical equations that proves that in a room of 23 or more randomly chosen people, odds are that at least two of them will have the same birth date.  When the group reaches 57, the probability of two people having the same date of birth reaches near certainty (99 per cent-plus).

It is counter-intuitive and hard for many of us to comprehend. This is, in part, because we  presume that one would need something more than 365 ¼ people to be certain of covering all of the days on the calendar more than once.  But this is the self-centered perspective that looks at the world and tries to estimate how many people would be needed to find one that shares our own birthday.

 George - Very much Alive
As you can see in rich and eye-reddening detail in the link above, the explanation lies in the point that we are not trying to match you or me, but you and me - or you and the other guy - or me and the other guy - or the other guy and some other person who just entered the room - or that new person with you -  or with me - as well as with the other guy - and on and on and on.

You soon see how many possibilities we have to couple people together – and why we have had enough coupling to produce over 7 billion people on earth.

The whole thing begs a funny blog, and one has been written (click here) .  So, I won’t try to write anything new about the Birthday Paradox (Proof again that  No ideas are new in the world of the Internet).

Today, however, I am thinking about the “Death Day Paradox” because on this date – November 4th – the ghosts of two people who have haunted my thoughts off and on for the last decade come together each year to visit me.  They both died on this day.

 Elsie - about 60 years before her passing
One is Elsie Gregory MacGill, a heroic woman of science and engineering, who was the first woman to earn professional credentials as an aeronautical engineer and aircraft designer, and the other is George J. Klein, the design engineer regarded as Canada’s most productive inventor.

I wrote Biographies of both of them, researched every little factoid on each, mulled the facts and figures around in my head daily, and yet somehow I did not notice that they shared the same date of finality until a few years after finishing the second book.

It struck me as eerie at the time and seemed like this tremendous coincidence.  If, I thought, you took a random sample of people whom I have written books about (not many) and calculated the odds of them having much more than me in common, it would have to be slim.

But this is another egocentric perspective, and maybe the coincidence is not so striking when you look at it in the light of the “Birthday Paradox” probabilities and stats and consider my definition of the sample size to be artificial and purely self-centered.

So- "Damn Interesting"  - as the Blog linked above says.

Well, maybe "damn interesting" just to me - because at this writing, a search of “Death Day Paradox” turns up only about a half dozen results on Google.  It could be that few others wonder about this issue because when you enter a room with 23 or more dead people, you automatically assume that they share the same or close to the same date of death.

Anyway, much more interesting are the lives of these two people – Elsie MacGill and George Klein.  Both were not plagued by self-centered quandries like the death day paradox and instead focused upon doing things and making the world a better place. Please learn about their achievements when you have the time.