# Intermission: A reminder … basic rules of probability

Please review the following posts on critical thinking and probability before proceeding.

Swede reminded me in the comments below yesterday’s post that coincidences just happen, and I should just accept that or something is wrong with my mind. Sigh.

Indeed they do. I’ve had some crazy ones. For instance, when we lived in Bozeman our neighbors up the road, Mark and Cathy, asked if I was related to Tom Tokarski. Indeed I was, as my brother at that time lived just down the road in Livingston. But they were talking about another Tom Tokarski, one who was their neighbor in Indiana and who was a citizen activist fighting to stop the building of a road though a local undeveloped area.

What are the odds, with maybe five Tom Tokarski’s in the country, that Mark and Cathy would be neighbors with one in Indiana, and then move a thousand miles away to be neighbors with the brother of another one in Montana? Very long indeed, but just one of those things. We have all had coincidences like that in our lives.

In the posts linked above, I am not talking about that, but rather the statistical likelihood of related coincidences. When coincidences have an event or person or place in common, we can apply some basic math to determine probability. It’s the logic of the coin toss, that’s all.

Please do go read those posts if you are having trouble understanding why, for instance,

• Charles Peirce was able to detect that a will was a forgery, or
• Why it is extremely unlikely that FOUR hijackings would be successful on a given day, or
• It is so unlikely that a hijacker’s passport would survive and be found in the rubble even as no parts of the plane survived, or
• That the surveillance system at the Pentagon, along with the national air defense system, would go haywire on the very day that Vigilant Guardian, the biggest national air defense military drill of the year was running.

(I have not yet mentioned the seventeen military and civil defense drills that were running on 9/11/2001, and how they were intricately connected to the events of that day.)

In other words, if you don’t have a basic understanding of probability, this won’t register with you. If you do have that understanding, it will trouble you.

## 5 thoughts on “Intermission: A reminder … basic rules of probability”

1. 100K flights a day X 365=36,500K/yr.X 20 years= 730,000K.

Chances of this highjack event in the last twenty tears 4 in 730,000,000.

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1. You do not understand probability and chance, and are making a fool of yourself here. I can take your comment down of you wish, as a favor.

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2. steve kelly says:

We have been sold story after story that we should fear consequences without ever considering probability. I deal with this constantly with the manufactured hype about wildfire used to manipulate minds into a fearful frenzy for the hidden agenda — clearcutting our public lands. Same tactics are used to market perpetual war. Without knowing probability, an accurate risk assessment is not possible, fear reigns.

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1. We recently sold a rental unit in Livingston, and we’re forced to put radon devices in the crawl space. That’s nonsense, a manufactured fear. When we sold our house in Bozeman, I refused to do that and the buyer agreed. But this time the renters were scared shitless (“what about the children“!) and we had to comply. Fear works.

The people who manufacture the mitigation equipment somehow infiltrated the regulatory agency, EPA, to put in ridiculously low levels as the standard. Even so, we are not required to abide, so the fear card is used to force our hand.

I swear, the American public is the most easily frightened group to ever live.

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