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Re: Matheology ? 222 Back to the roots
Posted:
Mar 1, 2013 5:11 AM


Nam Nguyen <namducnguyen@shaw.ca> writes:
> On 28/02/2013 7:51 PM, Virgil wrote: >> In article <khUXs.345339$pV4.177097@newsfe21.iad>, >> Nam Nguyen <namducnguyen@shaw.ca> wrote: >> >>> On 28/02/2013 8:27 AM, Frederick Williams wrote: >>>> Nam Nguyen wrote: >>>>> >>>>> On 27/02/2013 10:12 PM, Virgil wrote: >>>>>> In article <R8AXs.345282$pV4.85998@newsfe21.iad>, >>>> >>>>>> The set of all functions from N = {0,1,2,3,...} to {0,1,2,...,9} with >>>>>> each f interpreted as Sum _(i in N) f(i)/10^1, defines such a >>>>>> structure.. >>>>> >>>>> That doesn't look like a structure to me. Could you put all what >>>>> you've said above into a form using the notations of a structure? >>>> >>>> There is a set and a collection of functions on it. How does it fail to >>>> be a structure? >>> >>> From what textbook did you learn that a structure is defined as >>> "a set and a collection of functions on it"? >> >> Then give us your textbook definition of structure and show why the >> above fails to meet it. > > Shoenfield, Section 2.5 "Structures". One reason the above fails is, > you don't define, construct, the predicate (set) for the symbol '^'.
Who said that that is a predicate here?
> And that's just 1 reason amongst others. Do you admit it now that > the above fails to meet the requirements of a language structure?
It fits with Shoenfield in the case where the only predicate is equality.
 Alan Smaill



