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-   -   What the Tortoise Said to Achilles (http://www.physicsforums.com/showthread.php?t=449464)

murshid_islam Nov19-10 03:44 PM

"What the Tortoise Said to Achilles"
 
"What the Tortoise Said to Achilles" by Lewis Carroll: http://www.ditext.com/carroll/tortoise.html

What exactly is wrong with the logic here? Is anything wrong at all?

HallsofIvy Nov20-10 07:18 AM

Re: "What the Tortoise Said to Achilles"
 
No error. It is just noting that in order to accept any logical proposition as true, you must first accept the "rules of logic" as true. And, in order to do that, you must accept the rules used to construct those rules, etc.

That is why mathematical logic (I can't speak for philosophers) always starts with "given" rules and axioms.

Petek Nov20-10 10:59 AM

Re: "What the Tortoise Said to Achilles"
 
Also see the Wikipedia article on this topic.

Pretty Pony May20-11 04:28 PM

Re: "What the Tortoise Said to Achilles"
 
I don't understand what makes this story paradoxical. Can anyone enlighten me as to where there is a contradiction or otherwise?

HallsofIvy May20-11 05:36 PM

Re: "What the Tortoise Said to Achilles"
 
I see nowhere any mention of "paradox". Where did you get the idea that the story was "paradoxical"?

Pretty Pony May22-11 02:28 PM

Re: "What the Tortoise Said to Achilles"
 
Wikipedia refers to it as the Carroll paradox. It is included in Micheal Clark's book Paradoxes from A to Z as the Paradox of Inference. Thus I get the idea that the story was paradoxical.


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