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David Brightly
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Perhaps we Brits define ourselves by opposition to things Frenchified but I share Ed's misgivings. To be more specific, one of my concerns is this. As you use them, the terms 'fictional', 'intentional', 'possible', 'incomplete', and others like 'past' have a distinctive effect on the concept terms they qualify. Ordinary adjectives have the effect of narrowing the extension of the concept term they qualify: the red balls are a subset of the balls, the female prime ministers are a subset of the prime ministers, and so on. The terms in question have the opposite effect. They appear to widen, or indeed offset altogether, the extension of the qualified concept. They are thus potent alienating terms. So the question arises, What is the relation (if any) between the concepts 'fictional person' and 'person', between 'intentional object' and 'object', and 'possible X' and 'X'? Ordinary qualification can be uniformly understood in terms of set intersection. Is there a uniform explanation underlying these alienating qualifications? I say a bit more here.
Bill, Your definition RT gives us a causes relation over events. We could also define a brings about relation. I agree that without further premises x causes y does not entail that x brings about y. But can't the two relations have the same extension?
The lack of anything that necessitates my being awake now.
Hello Bill, I'm an anomalous trichromat. I think of normal colour vision as a rather finer grained version of my own, with, as it were, more 'places'. I understand what category of experience is denied me. My difficulty with anti-presentism is that I can't locate a 'place' for it in my intuitive geography. I appear to be denying something without any appreciation of what it is that I'm denying. I agree that 'Possibly, I am asleep now' is actually true, not merely possibly true, but I'm afraid I can't connect this to what I'm saying about using the subjunctive. I'm not asleep now though I might be. Hence my being asleep now must be numbered among the merely possible. I would render this as my being asleep is not but might be,a true conjunction of the indicative and subjunctive. I'm at a loss to see how this can be made stronger without falling into the falsehood of my being asleep is.So again I seem to lack the 'place' where you are standing.
Hello Bill, Convincing arguments against the ersatzisms. What I don't understand is why the actualist or presentist need find himself in such a tight corner that he turns to the desperate measure of conflating concrete and abstract. For the actualist can object to your (2), claiming it has the wrong mood and should be expressed asThe merely possible might not be nothing, ie, might be something.Likewise, the presentist can object that (2t) is wrongly tensed. It should sayThe merely past was not nothing.Both tetrads are then consistent.
Hello Bill, One of the ways in which ~∃t:T.ϕ(t) can be true is if the type T is empty. The mere formulation does not require that there be objects of the type. This is where I think your easy argument goes wrong. For a concrete example consider the standard proof that there is no rational square root of two. We start by saying Suppose there are such rationals; choose one in lowest terms, ie, numerator and denominator co-prime. But this, of course, turns out to be quantification over the empty set. The logic of my Caesar example is flawed. The inference is only good if Caesar was a Roman and Caesar crossed the Rubicon at the same time. Do you not think that the logic of untensed statements is rather weak? For Caesar (is) alive and Caesar (is) dead seem both true and there is no law of non-contradiction.
We are at the intersection of metaphysics and logic. >> But whatever we quantify over must exist: it must be there to be quantified over. Am I alone in not seeing that this is obvious? Some examples that suggest otherwise: 1. We agree that Caesar does not exist now. Yet we presumably agree that 'Caesar was a Roman' and 'Caesar crossed the Rubicon' are also true now and from these it follows by existential generalisation that 'Some Roman crossed the Rubicon' is also true now. Is this not quantifying over the presently non-existent? 2. 'One of my siblings is older than me.' This is meaningful but false---I neither have nor had any siblings---and ought to count as quantifying over the non-existent. But said by someone with an older sibling it would be true. 3. 'Frodo is a hobbit; Frodo went to Mordor; therefore some hobbit went to Mordor.' This is valid but unsound. But in some possible world it is sound too.
Bill, Could you confirm the following clarifications? 1. In the definition of the concept NPE 'present' should be bound to now, ie, a moment in the year 2013, rather than the moment of the concept's use. Thus there is a family of NPE-like concepts, one for each moment of time, and the one we are using in this discussion is NPE-2013. 'Socrates was NPE-2013' is true but 'Socrates was NPE-450BC' is false. 2. The P claim 'NPE is not instantiated' should be read as disjunctively detensed. That is, 'not NPE (is) instantiated', ie, 'not (NPE was instantiated or NPE is instantiated or NPE will be instantiated), ie, 'NPE was not, isn't, and will not be instantiated.' With these clarifications, P turns out trivially false, because as agreed in (1) 'Socrates was NPE-2013' and hence NPE-2013 was instantiated.
Following this discussion has been like living on a Möbius band: you go round a circle and fetch up where you started but the world is now upside down. Here is Markosian's opening paragraph. Presentism is the view that only present objects exist. According to Presentism, if we were to make an accurate list of all the things that exist – i.e., a list of all the things that our most unrestricted quantifiers range over – there would be not a single non-present object on the list. Thus, you and I and the Taj Mahal would be on the list, but neither Socrates nor any future grandchildren of mine would be included. And it’s not just Socrates and my future grandchildren, either – the same goes for any other putative object that lacks the property of being present. All such objects are unreal, according to Presentism. According to Non-presentism, on the other hand, non-present objects like Socrates and my future grandchildren exist right now, even though they are not currently present. We may not be able to see them at the moment, on this view, and they may not be in the same space-time vicinity that we find ourselves in right now, but they should nevertheless be on the list of all existing things.Although he hands over a hostage in his talk of 'unrestricted quantifiers' it's clear enough what he means by Presentism and Non-presentism and the contrast between the two, especially if we restrict ourselves to concreta. The census form asks us to give the names of the people who live in our house. Not the names of those who used to live here (difficult), nor of those who will live here (impossible). If 'exist' functions as a bona fide tensed verb then we know by analogy with the census instruction what Markosian is asking us to do. So much is obvious, commonsense, Moorean. So why is the non-presentist unhappy that the presentist has not included Socrates on his list? (This shows there is a disagreement before either party has tried to define his position in some mutually agreeable language) The answer, according to Markosian, is that NP has theoretical reasons for including Socrates. One, apparently, is that if Socrates didn't exist then propositions about him couldn't exist either, and this, according to NP, rules out our saying true things about Socrates, which we Mooreanly do. So NP has argued himself into a tricky corner. His way out is not to abandon his theory but to elaborate it further with the notion of 'tenseless verb'. To cap this he convinces himself that the whole discussion must be couched within his own theoretical terms and insists that the P must play on the NP's ground. The P will at this point refuse the invitation and concentrate on exposing the problems with the NP's theory. Consider this analogy to the present discussion. Rutherford tells us that the Mooreanly solid hand before our eyes is mostly empty space. How is this seeming impasse resolved? R explains that matter will be seen as solid (continuous) when viewed under visible light but discrete when viewed under much shorter wavelength radiation. This allows us to retain the meaning of our commonsense term 'solid' for our ordinary dealings with macroscopic objects in daylight. Likewise, if we are to take the NP seriously, then he has to explain how we are to live with his new tenseless verbs, eg, '(exist)', whilst keeping our old ones, eg, 'exist'. My own view is that NP faces formidable problems. Here's one: It seems that 'I (am) alive' and 'I (am) dead' are both true. So the law of non-contradiction seems not to apply to sentences using (is), and I, for one, will sorely miss it.
Bill says,We seem to have agreed that Disjunctive Presentism is a nonstarter: DP. Only the present existed or exists now or will exist. That is equivalent to saying that if x existed or exists or will exist, then x presently exists. And that is plainly false.Let's not abandon disjunctivism just yet. My suggestion is that the construction existed or exists or will exist isn't a proper verb and doesn't form a proper predicate. Rather it's a predicate schema in which the 'or' has sentence-wide scope. We should expand the schema as if x existed then x presently exists, or if x exists then x presently exists, or if x will exist then x presently exists,which is true. Compare with the quasi-colour 'green and black' in 'I like green and black olives'. If this is right then the tenseless '(exists)' which expands to the above construction has to be seen as a quasi-verb. Perhaps presentism really is trivially true but this clarity is muddied by the notion of tenselessness. More here.
Bill, In a comment on the 'Can a thing exist...' thread you say One cannot formulate the issue that divides the presentist and the anti-presentist unless one can somehow abstract from the temporal perspective of the present moment. One has to be able to 'survey' time analogously as one can survey space.With the idea of surveying in mind, is the following a reasonable suggestion? Imagine a discrete world in which the only changes take place at midnight. There is a fixed, finite number of predicates in our language and at any time a finite number of objects. We can thus denote time by day number starting on some arbitrary day, give each object a unique reference number on the day it comes into existence, and denote predicates by index numbers. Suppose on day number d predicate number p holds for object number n. We record this in a journal as the triple (d,n,p). This goes on until we reach day t, today. We can check the truth of assertions like 'object n satisfied predicate p' by running a decision procedure on the journal. The procedure for this particular assertion would presumably search the journal for a triple with second and third elements n and p respectively. We could ask presentist P to write procedures to check the truth of assertions of the form 'object n existed' or 'object n no longer exists'. By inspecting these procedures we would gain some understanding of what P means by these language terms. My questions are 1. For anti-presentist A, does the journal capture enough information about the world for this exercise to be useful? 2. If so, what procedure would A give us to check the truth of his statements of the form 'object n (exists)' and 'object n (has) property p'? 3. A could ask P to write a procedure to check that the journal's evidence confirmed his presentism. Would A accept that this elucidates what P's presentism amounts to (even if it turns out to be trivial)? I should perhaps add that these procedures have to be total in the sense that they give a definite answer when applied to the journal of any possible world that satisfies the above finiteness conditions.
Toggle Commented Mar 7, 2013 on Defining Presentism at Maverick Philosopher
Ed, Cryptic squared = Enigma
Morning Bill, Yes, I see the difference. But I don't accept that the presentist asserts RP with tenseless verbs. I think he really is offering us a tautology. If the verbs in your original argument are taken as tenseful then the resulting contradiction shows that some premise is false and the one to choose is obviously (3) though we might lay the blame at an objectual understanding of predication. On the other hand, if we take the verbs as tenseless then RP turns out obviously false and (3) as highly plausible. RP doesn't have to be a substantial metaphysical thesis for us to look at the argument either way. Tenseless predication is 'non-standard'. That's not to say it's inconsistent. I agree with Ed that how this new bit of language, '(verb)', is to work needs explaining in terms that we all understand, just as Robinson's non-standard real numbers or Lawvere's non-standard analysis are grounded in standard mathematical language. You ask us to think in terms of 'temporal locations'. That's no problem. Graphs with a time axis are a way of presenting all of time at once, as it were. You say If something is [(is)?]at one or more of these locations then it exists tenselessly. If it is also present, then we can say it exists (present tense).I take from this that 'x existed or x exists' is a sufficient condition for 'x (exists)'. If it's also a necessary condition then I think I have understood (exists), and I see no problem with it. Anti-presentism says no more or any less than presentism, it merely uses different language. But I suspect you will say, No, tenselessness reaches aspects of reality that tensefulness cannot reach. It is the Heineken of language. So we have arrived at our methodological differences once again.
Ed, The statementonly temporally present concreta existcontains two verbs. We should read it as if a concretum exists then it is temporally present.Reading both verbs as untensed and interpreting 'untensed' in your suggested way gets us to if a concretum exists or existed then it is or was temporally present,which is true. My working hypothesis as the moment is that presentist and anti-presentist are saying the same thing. It's just that the presentist is more fastidious about tense.
Thanks, Bill. I was going to ask you to give me a decision procedure for deciding the truth of untensed existence assertions given a putative History of the World. Your answer is just as effective and quicker! I am happy to think of time geometrically. It's been a remarkably productive idea. Your latest explanation leads me to think that 'X exists (untensed)' is equivalent to 'X existed (tensed) or X exists (tensed)', and this is indeed what I have been thinking all along. However, you appear to reject this suggestion (from Ed) in your (rather cryptic, if I may say so) comment of 01:33 PM . Will you perhaps say that these are extensionally equivalent but intensionally inequivalent? Or if they are extensionally inequivalent there should be an example that distinguishes them?
I'm sorry, Bill, you have lost me. Are you saying that there is a distinction between 'two plus two is (tenseless) four' and 'two plus two is (tenseless) four now'?
Peter, >> So what is wrong with... Could we return to your question later? Your remark that 'the second [is] restricted to the present, hence tensed' seems inconsistent with Bill's reply that all his uses of exist, including his (2), are tenseless. See my immediately preceeding comment to Bill.
Bill, I guessed that (2) 'Scollay Square does not exist now' was intended to be tensed because it contains the temporal qualifier 'now'. If our understanding of tenselessness derives from appreciating the timelessness of 'two plus two is four' then presumably the 'now' qualification makes no difference just as it makes no difference in 'two plus two is four now'. So (2) just says 'Scollay Square does not exist (untensed)' and we arrive at contradiction with (4). The remaining premise (5) which brings in presentism is superfluous. So I move to strategy (b): there is a fault in the reasoning.
Hi Peter, Yes, of course I accept the possible coherence of the two versions of exists. In fact I pretty much agree with Ed on how that coherence works. But I need to know which 'exists' is which! Ed, Thanks for the expansion! I suspect equivocation is where we are headed. Bill, Thank you. I take your point. Are my other guesses right?
Bill, If I have you right you are saying (comment at 04:34pm) that the following can all be true (and presumably are all true): 1. there is now no such philosopher as Quine. 2. there is (untensed) such a philosopher as Quine. 3. Quine exists (untensed). I would like to know a bit more about the notion of untensed verbs. One question I have is Does the notion of untensedness apply to 'ordinary' verbs? For example, can the following be true together 1. Tom no longer smiles. 2. Tom does not smile now. 3. Tom smiles (untensed). I have an inkling of what you might mean by 'Quine exists (untensed)' but not of what 'Tom smiles (untensed)' might mean.
Ed, You are missing what I took to be your own point made in the Scollay Square thread, and on which we seemed in agreement: >> 2. You deny that 3 (or 3A) is a logical truth. Therefore you deny that "R(a,b) therefore Ex R(a,x)" is a truth of logic? You are saying that "There is no such person such that John loves that person" is consistent with "John loves Mary"?? Suppose R denotes '_held hands with_'. John held hands with Mary does not imply that there is someone John held hands with. Mary may have died. It does imply that for someone, John held hands with that someone. It's a subtle difference in interpretation of '∃', which also explains the presentism/anti-presentism controversy.
Ed and Bill, Would you agree that '_was born on the same day of the year as_' defines a bona fide relation between individuals? Orlando Gibbons was born on the same day of the year as Isaac Newton (Christmas day actually), so surely we are entitled to say that said relation holds between Gibbons and Newton, though neither exists any longer? What does this make of Ed's 'logical truth' (3)?
Hi Ed, I think you have it too. I have a minor quibble but this looks like real progress. A is/was related to B implies A is/was and (B is or B was). I think we can restate what you are saying in terms of ∃. We must read '∃x.phi(x)' as 'for some thing temporarily called x, phi (x)' We must NOT read it as 'there exists an x such that...' or as 'there is an x such that...' The main verb is in the phi not the ∃ and may be tensed. Quantification, by default, is over the things that were or are. 'There is something that phis' translates to '∃x. x is and phi(x)'. So 'there is something that does not exist' translates to '∃x. x is and not x is' which is contradictory, hence false. Hence I agree with your (B) that there is nothing that does not exist. Your (A), 'some thing does not exist', follows by existential generalisation from 'Socrates does not exist'. As you imply, it takes a little practice to get used to this distinction. Unfortunately, E3 becomes If a relation obtains [between?] x and y, then y is a thing or y was a thing and this vitiates your argument. I agree regarding 'presentism'.
In Bill's formulation: In B3 the referent of the sentence's subject term is a description which may not be met, but the deduction at B7 assumes that it is. Alternatively, we could say that B3 implicitly assumes that referent-of () is a total function over sentential subject terms. This needs to be proved, or B3 needs an existential assertion in its consequent to the effect that the description is satisfied. In Ed's formulation: The converse of E3 is if y is not a thing then no relation holds between x and y. Thus we have no relation to our distant ancestors (who are presumably no longer things), yet the people who are our ancestors are in fact specified by such relations!
Well, shall we say that I now appreciate the distinctions you are drawing, Bill, and understand the associated jargon. Let me test myself... Consider a second carpet (c2) that's been stretched across a room whose floor is convex. As a result it has acquired curvature everywhere. This contrasts with our original carpet (c1) that is mostly flat but with local curvature at the bulges. Definition D1 allows us to say that both carpets have the accident of distortedness. We can now run an analogue of Lucas's argument in On the Nature of Accidents: Objections and Replies. The analogue argument would not be vulnerable to your counter argument (1) because, unlike colouredness, distortedness is not a necessary property of carpets (though this doesn't reflect my experience of carpet-laying). Argument (2), though not blocked, is rather weakened because c2 shows that distortedness can be present without bulgedness (unless you say that c2 is one vast bulge, which I reject because I say a bulge must contrast with a non-bulgy remainder). Distortedness is thus a genuine accident, at least of c2.
Toggle Commented Feb 16, 2013 on Defining 'Accident' at Maverick Philosopher