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Topic: A Point on Understanding
Replies: 66   Last Post: Jan 6, 2013 11:07 PM

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Joe Niederberger

Posts: 2,861
Registered: 10/12/08
Re: A Point on Understanding
Posted: Jan 1, 2013 8:18 PM
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PT III says:
>To provide the reader with some context so that he or she can see Keith Devlin meant, to see that he is not confused at all, here is part of what Keith Devlin actually wrote:
>"What Exactly is Multiplication?"
>http://www.maa.org/devlin/devlin_01_11.html


This is pretty funny and I can't pass it up. Following the above ref. to one of Keithe's columns, we find:
Keith D. says:
- --------------------------------------------------------
The MIRA fallacy becomes very apparent when you consider my second example, where I take an elastic band of length 7.5 inches and stretch it by a factor of 3.8. The final length of the band is 28.5 inches. But what are the units? What goes after the number 3.8 in the calculation

[3.8 - - -] x [7.5 INCHES] = 28.5 INCHES ?

The answer is nothing. It has no units. In this case, the 3.8 is a dimensionless scaling factor.
- ---------------------------------------------------------

He is writing far too fast here to consider his words. If no units are involved ("it has no units") then stretched inches of rubber band and un-stretched must be exactly the same to any commercial buyer. Same with puffed rice and uncooked rice. An inch is an inch. A cup is a cup. If I sell you 1000 yards stretched inches of rubber band you have no recourse if you expected 1000 yards UN-stretched. The very "nature of multiplication" declares you have no case!

Very funny indeed.

Cheers,
Joe N


Date Subject Author
12/15/12
Read A Point on Understanding
Robert Hansen
12/17/12
Read Re: A Point on Understanding
kirby urner
12/18/12
Read Re: A Point on Understanding
Robert Hansen
12/17/12
Read Re: A Point on Understanding
Haim
12/18/12
Read Re: A Point on Understanding
Robert Hansen
12/26/12
Read Re: A Point on Understanding
kirby urner
12/26/12
Read Re: A Point on Understanding
Robert Hansen
12/26/12
Read Re: A Point on Understanding
kirby urner
12/27/12
Read Re: A Point on Understanding
Paul A. Tanner III
12/27/12
Read Re: A Point on Understanding
kirby urner
12/27/12
Read Re: A Point on Understanding
Robert Hansen
12/27/12
Read Re: A Point on Understanding
kirby urner
12/27/12
Read Re: A Point on Understanding
Robert Hansen
12/27/12
Read Re: A Point on Understanding
kirby urner
12/27/12
Read Re: A Point on Understanding
Robert Hansen
12/27/12
Read Re: A Point on Understanding
kirby urner
12/27/12
Read Re: A Point on Understanding
Robert Hansen
12/27/12
Read Re: A Point on Understanding
kirby urner
12/28/12
Read Re: A Point on Understanding
Paul A. Tanner III
12/28/12
Read Re: A Point on Understanding
kirby urner
12/28/12
Read Re: A Point on Understanding
Paul A. Tanner III
12/30/12
Read Re: A Point on Understanding
kirby urner
12/30/12
Read Re: A Point on Understanding
Louis Talman
12/30/12
Read Re: A Point on Understanding
kirby urner
12/30/12
Read Re: A Point on Understanding
kirby urner
12/30/12
Read Re: A Point on Understanding
kirby urner
12/30/12
Read Re: A Point on Understanding
Paul A. Tanner III
12/30/12
Read Re: A Point on Understanding
kirby urner
12/30/12
Read Re: A Point on Understanding
Paul A. Tanner III
12/27/12
Read Re: A Point on Understanding
Domenico Rosa
12/27/12
Read Re: A Point on Understanding
Robert Hansen
12/27/12
Read Re: A Point on Understanding
Richard Strausz
12/27/12
Read Re: A Point on Understanding
Domenico Rosa
12/30/12
Read Re: A Point on Understanding
Joe Niederberger
12/30/12
Read Re: A Point on Understanding
Paul A. Tanner III
12/30/12
Read Re: A Point on Understanding
Robert Hansen
12/30/12
Read Re: A Point on Understanding
Joe Niederberger
12/31/12
Read Re: A Point on Understanding
Robert Hansen
1/2/13
Read Re: A Point on Understanding
kirby urner
12/30/12
Read Re: A Point on Understanding
Joe Niederberger
1/1/13
Read Re: A Point on Understanding
Paul A. Tanner III
12/31/12
Read Re: A Point on Understanding
GS Chandy
12/31/12
Read Re: A Point on Understanding
Robert Hansen
1/1/13
Read Re: A Point on Understanding
GS Chandy
12/31/12
Read Re: A Point on Understanding
GS Chandy
12/31/12
Read Re: A Point on Understanding
Robert Hansen
12/31/12
Read Re: A Point on Understanding
Joe Niederberger
1/1/13
Read Re: A Point on Understanding
Robert Hansen
1/1/13
Read Re: A Point on Understanding
GS Chandy
1/1/13
Read Re: A Point on Understanding
GS Chandy
1/1/13
Read Re: A Point on Understanding
GS Chandy
1/1/13
Read Re: A Point on Understanding
Robert Hansen
1/1/13
Read Re: A Point on Understanding
Haim
1/1/13
Read Re: A Point on Understanding
Joe Niederberger
1/1/13
Read Re: A Point on Understanding
Joe Niederberger
1/1/13
Read Re: A Point on Understanding
Paul A. Tanner III
1/1/13
Read Re: A Point on Understanding
Louis Talman
1/2/13
Read Re: A Point on Understanding
Paul A. Tanner III
1/1/13
Read Re: A Point on Understanding
Joe Niederberger
1/2/13
Read Re: A Point on Understanding
Paul A. Tanner III
1/2/13
Read Re: A Point on Understanding
GS Chandy
1/2/13
Read Re: A Point on Understanding
Joe Niederberger
1/4/13
Read Re: A Point on Understanding
Joe Niederberger
1/5/13
Read Re: A Point on Understanding
GS Chandy
1/5/13
Read Re: A Point on Understanding
GS Chandy
1/6/13
Read Re: A Point on Understanding
Robert Hansen
1/6/13
Read Re: A Point on Understanding
GS Chandy

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