From: Brian Holtz [brian@holtz.org] Sent: Wednesday, May 29, 2002 8:20 AM To: alt.atheism.moderated Subject: Re: Science & atheism are cultures. "Jesse Nowells" wrote: > > How do you distinguish between possible worlds and "the actual > > ones" that are not this one? > > Hypothetical actual worlds *are* possible worlds. "Hypothetical" is your word here, not mine. Are you saying that ours is the only actual world? > > The same could be said of "actual" worlds that are not this world. > > You're talking about *possible* actual worlds. I'm talking about the set of worlds that are not only possible but are also actual. Are you claiming this set has only one member? > > What's precisely "nonsense" is to claim that there is a difference > > between other possible worlds and other actual worlds without being > > able to say what that difference is. > > You can't if they are in fact only possibilities. You're equivocating on > "possible worlds" & "actual worlds". No, you're just retreating from the idea that any other world could be actual, and thus conceding my point that, when applied to worlds, 'actual' means 'this'. > > what precisely does 'existence' (or 'actuality') mean when > > applied to worlds, and how is it different from possibility? > > There is no difference between possible worlds & possible actual worlds. Are you saying there is no difference between other worlds that are merely possible and other worlds that are indeed actual? If so, then you're agreeing with everything I've said. > > No, I'm just noticing that 1) the ontological term 'exist', > > when precisely defined, only applies within worlds and not > > to worlds themselves; and 2) the ontological phrase 'the actual > > world' just means "this world". > > (1) is an assertion w/o an argument. You don't state this "precise" > definition. I have; you just came in late, and haven't bothered to catch up. As I quoted earlier from my book: "To exist is to have a causal relationship with the rest of the universe." Clearly, this applies within worlds and not to worlds themselves. > Exist means "to have a place in objective reality". You're just defining 'existent' with its synonym 'real'. Try defining 'existent' without any of its synonyms. > "world" is ambiguous. Not in its traditional philosophical usage of "possible worlds". As I wrote in this thread on Mar 23, the philosophical notion of a possible world means something like what in logic is called a "model": a set of well-formed formulas associated with 1) a non-empty set of objects/things/entities (the domain), and 2) a mapping of all the constants, predicates, and functions in the wffs to constants, relations, and functions defined in the domain. An even closer idea is the ontological notion of a universe: the transitive closure of some circumstances and events according to their causal relatedness. > Objective reality is evidently independent of the mind If observers can count as "minds", then quantum theory provides some exceptions to this general rule. > > if something's existence is in principle absolutely > > impossible to know or observe in any way, then a proper ontology > > should hold that it does not exist, even if someone stipulates > > otherwise. > > You can't presume that if something is not known that therefore it does > exist or not exist. That's not what I presume. You've weakened my "in principle absolutely impossible to know or observe in any way" to your "not known". > You only assert that exists applies only within worlds. You don't have a > clear definition of the term world Yes I do; see above. > > I'm still eagerly waiting to hear the difference between 'possible' > > and 'actual' when applied to worlds. > > What you got going here is an equivocation on the terms possible & actual What I have here is the opposite of equivocation: rather than using (in the domain of worlds) two different definitions for either of these two terms, I'm saying that (in the domain of worlds) they each share the same single definition. > because worlds outside of the known world are speculations That something's existence is speculative should not prevent one from describing what in principle distinguishes it from other things that one describes with different terms. -- brian@holtz.org http://humanknowledge.net