The Slow-Seeming Snapping Turtle

(Don’t Judge a Book by its Cover Story)

One find summer day, driving down the long curved driveway of IBM Research in Yorktown, I noticed a manhole-sized snapping turtle in the middle of the driveway. I pulled the car over. I didn’t want someone running into the reptile, looking as he did, such a splendid living fossil. 

Naturally, I knew snapping turtles could be dangerous, though as I watched him plod ever so slowly down the road, I felt no threat. Surely, my mammalian reflexes were far superior to this reptilian beast. But, in a seeming excess of caution, I made no attempt to touch him with my bare hands. Instead, I found a thigh-sized dead tree branch that seemed suitable for pushing him off the road and thus to safety. 

I pushed hard on one side of his carapace. At first, he just kept plodding ahead, but my superior strength overcame his squat stubborn frame and he gradually angled toward the berm. Then, an unbelievable thing happened. In a split second, the viscous snapped to vicious. His head shot out a good foot from his shell and whipped around to the side, still managing his neck-lengthening trick. He chomped down and completely through the tree limb before I even had a chance to be startled. 

Our first impression of a situation can often lead us to dangerously erroneous actions. 

Here’s another example. 

As most Americans now know, there are 435 people in the House of Representatives. What is the probability that at least two in the House of Representatives share a birthday?

This is actually an exceedingly easy problem to solve. 

Unless…

Unless, you are familiar with a similar-looking problem called “The Birthday Problem” which may be stated something like this:

You are starting a new class of thirty people. What are chances that at least two of them share a birthday? 

https://en.wikipedia.org/wiki/Birthday_problem

It turns out that at least two people will share a birthday in a room with 30 random people over 70% of the time. The “break-even” point where the chances that at least will share a birthday is 23 people. It’s a bit counter-intuitive. But the math is sound. 

So, if you have heard of “The Birthday Problem” before, and heard the question about The House of Representatives, you’d be likely to say something like: “Oh, that’s the birthday problem and it turns out you don’t need many people for their to be a likely double birthday. So, with 435, it must be very hight. Perhaps 99% or even 99.9%”

With 435 people in The House of Representatives, you don’t need to “calculate” any probabilities at all. You cannot arrange any way for more than 365 people to “fit into” 365 days without starting to overlap. 

Beware of approaching problems (or snapping turtles) based on their eternal appearance. It might or might not be a good clue to its actual behavior. 

In the Pattern Language for Collaboration, one is based on this called “Context-Setting Entrance.” Because we are prone to pay attention to the entrance, then if we design one, we should let that entrance set appropriate expectations. 

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Author Page on Amazon 

The Winning Weekend Warrior focuses on the mental game for all sports.
http://tinyurl.com/ng2heq3

Turing’s Nightmares explores the possible futures of how people communicate with computers and each others. http://tinyurl.com/hz6dg2d

Fit in Bits describes many ways to work more exercise into daily activities. http://tinyurl.com/h6c7fce

Tales from an American Childhood recounts early experiences and relates them to contemporary issues and events. https://tinyurl.com/y9ajvz9j

Beware of Sheep in Wolves’ Clothing