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Bob's Books
pauldeegan
Topic Author
pauldeegan created the topic: Bob's Books
Just wondering if anyone can tell me...
there is a phrase in one of Bob's books. I think its a Latin phrase that says look at the extreme case. Or look at the absurd case to find the answer.
and which book is it in
Just sitting around having a couple of beers talking and the words didn't come out because I forgot!
The phrase you're looking for is "Reductio ad absurdum". It's a way to disprove an argument. You follow the implications of the argument to an extreme case to show the absurdity of the original premise.
I can't tell you which book it is in though. That could be a treasure hunt for someone
I used that argument in the Aerodynamics book to prove the extistance of molecules or atoms. Imagine that you took a given quantity of any element and cut it in half, then took one of those halves and cut it in half again, then took one of those smaller halves and cut it in half again, If you continued that procedure indefinitely, what would be the final outcome?
Either there would be a piece that is so small that it could no longer be halved - a fundamental particle, or there would be a piece that was so small that half of it would be nothing at all.
The second possibility is absurd, because if the partical was made of two halves of nothing, then it never existed in the first place!!
So there must be a fundamental particle that can no longer be halved. Of course we now know that even that particle can be broken down into even smaller components [electrons, protons and neutrons] but when that happens, it is no longer the original material. The original sample must have been made up of many millions of those fundamental particles.
Yes. In the case of the wind effect you consider what would happen in the extreme case when the headwind or tailwind equalled your TAS. How far from base could you fly before you could not get back?
In the case of the headwind you would never get anywhere; and in the case of the tailwind, if you left the base aerodrome, you would never get back.
