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03-27-2003, 08:29 AM | #21 | ||
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Originally posted by HRG :
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More generally, it certainly seems true to me that everything that exists satisfies some predicate(s), and that there's a primary-kind property "being God." It's not as if we're limited to within the predicate calculus for our description; successive translation of the elusive sentence in question would simply read "There is only one being that instantiates Godness," and then "There is only one God." We can certainly understand the meaning of these sentences, and that suggests to me that if they're direct translations of the sentence in the 1st-order predicate calculus, that sentence is meaningful as well. |
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03-27-2003, 10:19 AM | #22 | |
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I think we have an equivocation fallacy going on here. You seem to be reading ‘true in all possible worlds’ as ‘true in all formal systems of logic.’ However, in terms of modal logic, at least as it is commonly used by philosophers, ‘true in all possible worlds’ means ‘true in all logically coherent states of affairs.’ Those are two completely different meanings. God Bless, Kenny |
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03-27-2003, 02:34 PM | #23 | |
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First of all, I disagree that the statement “there is a logically possible world in which God exists” literally means that God exists in every possible world. In order for such to be the case, the former would have to entail, without the help of any additional premises, the latter. But clearly “there is a logically possible world in which God exists” does not entail that God exists in all possible worlds unless we add the premise that if God exists God necessarily exists. Otherwise, the ontological argument would only require one premise rather than two. Second, I don’t see why it should necessarily be any more difficult to prove that God exists or any “harder” for God to exist than it would any other necessary truth to be true. Consider, for example, the statement “2+2=4.” I think that there are good philosophical arguments for accepting the premise that if “2+2=4” is true at all then necessarily 2+2=4. First, it is clear, however, that 2+2=4 does not literally mean that necessarily 2+2=4. In fact, there are some philosophers who accept the former while rejecting the latter (though I am aware of none who reject both the former and the latter ). Second, it's very easy to prove that there is a logically possible world in which the statement “2+2=4” is instantiated. I recall doing so sometime in my very early childhood (at the age of five or six perhaps?) by counting on my fingers. I don’t see how a proposition’s being necessary entails that it is somehow more difficult to prove. Nor do I see that it is somehow “harder” (I’m not even sure what that would mean in this context) for the statement “2+2=4” to be true simply because it is necessary. God Bless, Kenny |
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03-27-2003, 05:17 PM | #24 |
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Earlier, I wrote:
"There is a possible world in which maximal greatness is instantiated." To which Thomas responded: ______________________________ I don't like that formulation, because then the statement seems to me to be patently false. Maximal greatness can't be instantiated "in" a possible world, because what's in the world itself has nothing intrinsically related to other possible worlds. ______________________________ The reason I introduced this way of stating the premise was to hedge out problems that arise in modal contexts when singular terms occur in negative existential statements. In any case, you take umbrage with the convention of locating property instances in (or at) worlds. I don’t know what mileage you hope to gain by adopting that stance, or how it is relevant to your earlier suspicions about the difficulty in accepting one modal premise over another, so feel free to clarify. Its also somewhat puzzling that you take an opposing stance, and then appear to grant the conventional usage later in the same post. ______________________________ Maximal greatness doesn't exist in possible worlds; it ranges over possible worlds. ______________________________ It appears we differ substantially on the terminology and concepts involved, so we should address those issues. As I see it, If we take a (broadly) realist stance on properties, and possible worlds (as initially sketched by Kenny), and we take maximal greatness as a property (actually, a conjunction of *world-indexed* properties), then we would certainly want to say that maximal greatness, (or any other property for that matter), exists in (or at) a world. Of course a distinction will be made between a property *existing* in a world (or all the worlds) and a property being *instantiated* at a world. The issue surrounding the "existence” of the property of maximal greatness then, is not to the point. ______________________________ Just in case the argument is presented with that statement as a premise, I offer the alternatives: "There is a possible world in which maximal greatness is not instantiated." "There is a possible world in which 'exists necessarily' and 'is a unicorn' are satisfied by the same object." I see just as much reason to accept these propositions as I do to accept their cousin. ______________________________ These are interesting claims, and ones worth exploring. I then wrote: "I'm not sure that its "hard to support the modal premise", if we understand it in terms of possible property instantiation. As Kenny suggested earlier, it seems quite reasonable to say that the premise is (at worst) properly basic for some people." To which you respond: ______________________________ I think the illusion of proper basicness occurs because of a confusion between epistemic and alethic modality. "There is a possible world in which maximal greatness is instantiated" is true if "possible" is epistemic possibility, but we have no way to tell whether it's true if "possible" is alethic modality. ______________________________ I assumed it was understood that when theistic philosophers talk about “possibility” with regard to the modal ontological arguments, they typically have Broad Logical Possibility firmly in mind. This understanding of modality is to be distinguished from other types of “possibility”; Narrow Logical Possibility, “epistemic” possiblity, as well as wider notions like nomological and “physical” possibility. Given these distinctions, I’m not sure where you think that “confusion” arises with regard to a persons belief regarding modal propositions, in this broadly logical sense. You claim that “we” (you?) have no way to tell whether a given proposition or its negation is true, but neglect to expand on why you think that is so, or why it is true for others. ______________________________ When you evaluate your intuitions about the alethic version, ask yourself whether your intuitions suggest that maximal greatness is instantiated in all possible worlds, because that's what the statement literally means. ______________________________ That’s as good a piece of advice as I’ve received in a while Regards, Bilbo. |
03-28-2003, 01:54 AM | #25 | |||||
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If someone talks about "water" as a "natural kind word", he is not doing philosophy, but linguistics, cognitive psychology etc. Quote:
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regards, HRG. |
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03-28-2003, 02:10 AM | #26 | ||||
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If you had "added" 2 drops of water to 2 drops of water, you'd have gotten a (bigger) drop. Thus, numbers plus addition model the behavior of fingers, nuts or dimes, but they do not model the behavior of drops. The distinction between "2+2=4" and "2 fingers juxtaposed to 2 fingers make 4 fingers" may sound trivial, but it isn't. It is the same as a distinction which is made since Gauss, Riemann and Einstein: mathematical geometry (that which is deduced from axioms) versus physical geometry (that which described the behavior of rigid rods and light rays). That the former (in its Euclidean version) models the latter to a good approximation does not prevent the essential distinction between the two. Regards, HRG. |
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03-28-2003, 12:52 PM | #27 | ||||||||
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This thesis is supported by the fact that individuals can actually refer to objects even when they have a completely false concept of them. One of Kripke’s own examples is to suppose that there is a man in the street whose only conception of the term ‘Godel’ is ‘the man who originally proved the incompleteness of arithmetic.’ Now suppose that, in fact, Godel plagiarized his famous incompleteness theorem from some other man, say Smith. The man on the street still refers to Godel (and says something false about him) even though his concept of Godel is actually wrong. Likewise, he does not refer to Smith, even though Smith actually fits his conception of ‘Godel.’ Quote:
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Likewise, when we say "the substance which fills the Earth’s oceans may not have been the substance which fills the Earth’s oceans” the first occurrence of ‘substance which fills the Earth’s oceans’ means ‘water’ whereas the second occurrence of ‘substance which fills the Earth’s oceans’ ranges over counterfactual scenarios in which some other substance besides water fills the Earths oceans. If this counter factual scenario had been realized, the substance which fills the Earths oceans would not have been water. That’s easy to confirm intuitively. Suppose some sufficiently powerful being were to empty the Earth’s oceans and replace their contents with NH3 molecules. We would then say that the Earth’s oceans no longer containe water, not that water is now composed of NH3. Quote:
Now suppose that some English speaking scientists from Earth were transported to Twin Earth. On first impressions, having been told by be the inhabitants that what fills the lakes and rivers of Twin Earth is water, the scientists assume that the word ‘water’ on Twin Earth has the same meaning that the word ‘water’ does on earth. However, upon testing, the scientists discover that what is called ‘water’ on twin earth is actually composed of XYZ rather than H20. Putnam believes that the conclusion these scientists would draw (or at least should draw) is that what is called ‘water’ on Twin Earth isn’t water. Likewise, scientist from Twin Earth could say, in their dialect, “What is called ‘water’ on Earth, isn’t water.” This is because, although the two words ‘water,’ on both planets are identical in terms of spelling and phonetic sound, they are actually two different words with two different meanings with the meaning of the spelling or utterance of ‘water’ being determined by the dialect of the speaker or the writer. Now suppose we rewind the history of Earth and Twin Earth so that we are at a time when the scientists on these planets have not yet discovered that the substance which each refers to as ‘water’ is composed of H2O or XYZ respectively. It would still be the case that what Twin Earthers refer to as ‘water’ differs from what Earthers refer to as ‘water.’ Its easy to test our intuitions against this. Suppose, in the real world, scientists were to discover the substance XYZ and initially mistake it for water. Upon finding out that it this substance consisted of XYZ molecules, the scientists would conclude that the substance they had discovered was not water but something else. They would not conclude that water could be composed of XYZ rather than H2O. Similarly, suppose a scientifically unsophisticated speaker (a child perhaps), in the real world, on Earth, who is unaware that water is composed of H20, mistook a flask of XYZ for a flask of water. We would want to say that said speaker’s identification was incorrect. Quote:
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Now, certain terms like ‘water’ Kripke argues, can only be used as rigid designators. ‘Water’ means precisely what can be abstracted from the set of representative exemplars referred to by a certain social linguistic community as ‘water.’ We can not say, with propriety, “Water might not have been water” because there is no room for the scope of the word ‘water’ to change from rigid to non-ridged. In Putnam’s terminology, ‘water’ is a natural kind word. Likewise, since the word ‘water’ obtains its meaning from its representative exemplars, water is genuinely identical with the set of properties all of those exemplars share in common, and consequently water is identical to H2O. This is true whether the speakers are aware of this identification or not. And it follows from the fact that there can be no genuine contingent identity statements that Necessarily, water is H2O. Quote:
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God Bless, Kenny Whew, how do I get myself into making such long posts like this when I only want to make a few brief comments? You think I would have learned my lesson by now. |
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03-28-2003, 02:06 PM | #28 |
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HRG, I was going to come here and invite you to join the Aquinas thread but am happy to see that you have already done so. It needs new blood.
I also notice that you carry over your confusion regarding the competency of modern science. I don't know yet if this is completely fair to you. But I knew without you saying that you suspect "ontological classifications" are just mental constructs. This, at least, makes you interesting and gives you grounds to discuss such things as Aquinas' concept of esse. On second thought, though, you might not be at home in the Aquinas thread. It depends on just how agnostic you turn out to be concerning metaphysics. Regarding this thread, 1) it would be nearer the mark to say that an infinite series IS the contingency problem, 2) my statement about temporality and causation does not imply the identity of concepts you suggest, 3)science, though only in your humble opinion, is not capable of tackling the Thomistic proofs--as I have argued elsewhere, descriptive, natural science takes the being of things for granted, not addressing the why that concerned previous generations (like Aristotle's) but the what of things. Aquinas, also, did not adopt the peculiarities of Aristotle's notion of Prime Mover as Final Cause, for example, and does not depend for its validity on contemporary science. . . . But your perspective gives us something to talk about, which we might end up doing in the Aquinas thread. |
03-28-2003, 06:28 PM | #29 |
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This is a fine exposition of the so called "New Theory of Reference" as that theory pertains to natural kind identities. I’ll just chime in with a footnote or two
Kenny writes: --------------------------------------- First, the law of substitutive identity says that, for any objects x and y, if x is identical to y, then if x has a certain property F, so does y: (1) (x)(y)[(x = y) -> (Fx -> Fy)] On the other hand, every object surely is necessarily self-identical: (2) x) [](x = x) But (3) (x)(y)(x = y) -> [[](x = x) -> [](x = y)] is a substitution instance of (1), the substitutivity law. From (2) and (3) we can conclude that, for every x and y, if x equals y, then it is necessary that x equals y: (x)(y)((x = y) -> [](x = y)) --------------------------------------- A little more intuitively and informally, we can speculate just which pairs invalidate the above formula (actually a theorem of Ruth Barcan’s, later revived by Kripke). Certainly not two different things (for then the protasis is false) and certainly not the same thing (for then the apodosis is true). quote: -------------------------------------------------------------------------------- I can imagine an Earth, under different physical and chemical laws, whose oceans are mainly composed of NH3. -------------------------------------------------------------------------------- --------------------------------------- Its easy to test our intuitions against this. Suppose, in the real world, scientists were to discover the substance XYZ and initially mistake it for water. Upon finding out that it this substance consisted of XYZ molecules, the scientists would conclude that the substance they had discovered was not water but something else. They would not conclude that water could be composed of XYZ rather than H2O. Similarly, suppose a scientifically unsophisticated speaker (a child perhaps), in the real world, on Earth, who is unaware that water is composed of H20, mistook a flask of XYZ for a flask of water. We would want to say that said speaker’s identification was incorrect. --------------------------------------- One of the unfortunate aspects of Putnam’s Twin Earth thought experiment is that the terms “water” and “H2O” typically function as mass nouns, (rather than count nouns), and mass nouns are ambiguous and incomplete when used in identity statements. After all, the chemical formula “H2O” is a simplification and an approximation of what water is. Because some substance isn’t literally H20 (according to one sortal specification), doesn’t necessarily mean that it isn’t water. Putnam conceeds this point in a later essay (“Possibility and Necessity”, in volume three of his collected papers), but emphasizes that the identity relation, or in this case – “similarity relation”, is still one of necessity, IF true. So if it really is possible that water is XYZ in Twin Earth (ie Broad Logical Possibility), then water is not H2O on our earth, or any other earth for that matter (contraposition). Or, alternatively, if our present molecular theory does not accurately model The Real World, then we might one day come to realize that water was not-H20, indeed, that its impossible that water be H20. --------------------------------------- And it follows from the fact that there can be no genuine contingent identity statements that Necessarily, water is H2O. --------------------------------------- As I see it, the salient point with regard to this theory is that the proponent shouldn’t be viewed as making questionable, extravagant or suspiciously unscientific claims with regard to the necessary a posteriori, because the necessity in question is qualified, and in one sense relative to our common opinions about what is actually the case. --------------------------------------- Whew, how do I get myself into making such long posts like this when I only want to make a few brief comments? You think I would have learned my lesson by now. --------------------------------------- An excellent and satisfying post Kenny; if we can be pardoned for (temporarily) losing God in all this Regards, Bilbo. |
03-28-2003, 10:11 PM | #30 | ||||
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Originally posted by Bilbo :
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"There is an alethically possible world in which maximal greatness is instantiated." But we know that this proposition is true: "There is an epistemically possible world in which maximal greatness is instantiated." When I say we have no way to tell whether the former is true, I only mean in practice. I don't know whether there is a sound argument for the existence of the Anselmian God, so I don't know whether we have epistemic access to the truth of the former in principle. |
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