Re: Skolem Again



On 9 Oct 2005 08:51:15 -0700, William of Ockham
<d3uckner@xxxxxxxxxxxxxx> said:
> If I make a mistake, please tell me what's wrong.

ok, but I sorta thought that's what I and others have been doing.

>> It's about the implications of a technical result of which you
>> are ignorant.
>
> And which I am trying to understand, both by finding the'right'
> textbook, and from what you are saying. I apologise if anything I say
> comes off as 'spouting'.

By which I only meant "going on at length".

>> Most of your confusion arises from the fact that you are having
>> such trouble distinguishing truth from truth in a model.
>
> As I understand, "S is true in M" means that the state of affairs said
> to exist by S, is included in M.

But why do you insist on understanding it like that? "S is true in M"
has an *extremely* precise meaning in model theory, which is essential
to having a good grasp of the L-S theorem. There are no such things as
states of affairs in model theory *at all*.

> I don't know what 'true' means.

Well, in this context, true in the universe of sets, which is a species
of truth in a model (modulo some set/class issues that I'll ignore
here). The point, again, is that many of our theories are designed to
characterize as far as possible one specific model, or perhaps a class
of structurally similar models, and by "truth" we mean truth in *them*.

>> Do you mean, a given interpretation may result in "x is uncountable"
>> being true of some set of things of which it is 'really' false?
>
>> True *in some model* of some set of things of which it is "really"
>> false.
>
> It's the 'really' I am having trouble with. Why do you put scare
> quotes around?

I was simply following your lead. They add nothing.

.



Relevant Pages

  • Re: The truth of evolution
    ... state of affairs. ... Rorty doesn't believe there is any absolute truth. ... Rorty's a pragmatist so I doubt he would adopt the fairy shoe ... increases the sum of happiness. ...
    (uk.philosophy.humanism)
  • Re: logical paradoxes
    ... >> And as Bateson would say, the reason why classical Aristotelian logic ... both too much and too little for handling the Liar ("This sentence is ... It's too much because in model theory, every ... proposition has a fixed truth value in each interpretation. ...
    (sci.logic)
  • Re: Gallup Poll: Two-thirds of US Are Creationists [Atheists Lose, Again]
    ... Its a sad state of affairs when the Lack of "truth and knowledge" ... provide the environment for myth. ...
    (alt.politics)
  • Re: All panduks are green
    ... of saying it has no truth value, when we have a perfectly good ... Similarly "a sentence is meaningful iff it is a picture ... of a possible state of affairs" is a sensible definition. ... unicorns are NOT green" is not true either. ...
    (sci.logic)
  • Re: model theory: Whats the big picture?
    ... I'm also not clear on why model theory is needed in order to define ... that's not already present in that notion of mathematical truth? ... A theorem of formal theory with symbols, syntax, axioms and rules of inference, is a formula that is the last in a sequence of formulas, each of which is either an instant of a axiom of the result ... model-theoretic truth value and provability. ...
    (sci.logic)