>
> In a message dated 99-10-01 07:28:42 EDT, Bruno Marchal writes:
>
> >>I would like to add something about LIP (Leibnitz Identity Principle) :
> >>I accept it in non-modal (extensional) context. For exemple if you tell me
> >> that a = 3, I accept that a + 1 = 4.
>
> >>But I don't accept it in modal (intensional) context. For exemple if you
> >> tell me that a = 3, I will NOT infer that "Jean knows that a + 1 = 4", for
> it
> >> is possible that although a = 3, Jean doesn't know it.
>
> >>What I have said in my last post follows from the fact that the 1-person
> >>and 3-person notion introduces modal contexts.
>
> >>Listen, people, I don't belief you can keep talking about worlds and
> >>observers without using a minimal amount of MODAL LOGIC.
> >>I told you that before.
>
> I agree Bruno, I don't know much about modal logic and I'll try to brush up
> on it. From what you wrote above, you are saying that LIP (Leibniz
> Indistinguishability Principle) comes in two flavors.
>
> The first is the non-modal extensional version which says that if two
> particular items appear indistiguishable to an observer, then in so far as
> this observer is concerned, these two items are one and the same. However, he
> cannot conclude that these two items will appear indistinguishable, and hence
> be identical to other observers. This conclusion is very much in keeping
> with Relativity Theory.
>
> The second version of LIP is the modal intensional version. It says that if
> two items appear to be indistinguishable to an observer, then these two
> items, not only are identical insofar as the observer is concerned, but are
> also indistinguishable and identical to other observers. This version
> supports a view of the world which is absolute.
>
> It seems that if we extrapolate the above, we are heading toward having to
> decide whether reality is subjective and relative, or objective and
> absolute. Extrapolating still further, we are led to having to make a choice
> between a Many-Perspectives Interpretation and a Many-Worlds interpretation.
> The Many-World Interpretation would support an objective world independent of
> the consciousness that inhabits it; and the Many-Perspective Interpretation
> would consider each SELF as the center of its own universe (perception) -
> kind of like a distributed solipsist point of view. The only absolute entity
> in the Many-Perspective Interpretation would be the Plenitude itself.
>
> George Levy
>
>
Hmm... I would for the most part follow the many perspective
interpretation, however I consider that perspectives without conscious
observers may also be considered to exist, (in as much as they are
self-consistent) in that they may be able to be imagined by conscious
observers elsewhere in the plenitude.
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Received on Mon Oct 04 1999 - 22:45:06 PDT