• A Case for Moral Anti-realism
    What will he say to you? What will you say to him? Will it be sufficient to tell him that you "chose not to" meet with him?Leontiskos

    Sufficient for what? I don’t really understand the question or how it relates to my comments to Banno.
  • A Case for Moral Anti-realism
    Right, and is it not also true that if a promise is sincere then one will do what they promised (unless some unforeseen impediment intervenes)?Leontiskos

    No, because I may choose not to, i.e. I changed my mind.
  • A Case for Moral Anti-realism
    Why can't you?Leontiskos

    Because a promise is sincere only if one intends to do as one promises.
  • Infinite Staircase Paradox


    Huh? I'm reiterating/agreeing with your claim that "it doesn't matter whether you put the halving ad infinitum as an antecedent in a conclusion or as a premise - it's logically the same"?
  • Infinite Staircase Paradox
    It doesn't matter whether you put the halving ad infinitum as an antecedent in a conclusion or as a premise - it's logically the same.TonesInDeepFreeze

    Yes, it makes no difference if it's an antecedent in a conclusion or as a premise. Either way, the supertask is the completion/end of an infinite/endless sequence within finite time (e.g. I have stopped pushing the button by 12:00) and is an inherent contradiction, irrespective of what the task is. Having the task be to push a button that turns a lamp on and off is just a means to demonstrate the impossibility of a supertask and not the reason for its impossibility, and neither having the button be broken nor having the lamp spontantously turn into a pumpkin allows for the supertask to be possible.
  • Infinite Staircase Paradox
    But completion is not in your premises.TonesInDeepFreeze

    This is my argument.

    Notice the antecedent of C6: "If the button is only ever pushed at 11:00, 11:30, 11:45, and so on ad infinitum...".

    If I am only ever pushing the button at these times then I am not pushing the button at 12:00 or at any time after 12:00. Therefore, my (infinite/endless) button-pushing has ended by 12:00.

    That's what supertasks are. They are an inherent contradiction, irrespective of what pushing the button actually does. It is as metaphysically impossible to have performed a supertask on a broken button as it is metaphysically impossible to have performed a supertask on a working button. Having the button turn the lamp on and off, like killing my grandfather before my father is born, is just a means to better demonstrate this impossibility and not the reason for it.
  • Infinite Staircase Paradox


    P5 is an inherent contradiction, just as travelling back in time is an inherent contradiction.

    The lamp being neither on nor off at t1 and killing one's own grandfather before one's father is born are secondary contradictions to prove the inherent contradictions.

    The possibility of P5 does not depend on whether or not P1-P4 are true, e.g. having the button be broken does not make it possible to push the button an infinite number of times within two hours.
  • Infinite Staircase Paradox
    The definition of a super-task is as you say. But your listed premises don't say anything about completion or ending.TonesInDeepFreeze

    The infinite button pushes ends after two hours. That's the premise of Thomson's lamp (albeit minutes in his specific case). In his own words, "after I have completed the whole infinite sequence of jabs, i.e. at the end of the two minutes, is the lamp on or off?".

    If, as per the premise, I only push the button at 11:00, 11:30, 11:45, and so on ad infinitum, then I am no longer pushing the button at any time after 12:00. My infinite button pushes has allegedly ended.

    The very thing we're discussing is the possibility of supertasks, i.e. can an infinite sequence of operations end in finite time?

    The contradiction is: The lamp is either On or Off T 12:00 and the lamp is neither On nor Off at 12:00.

    But that contradiction comes from a set of premises, each of which is not logically true, and dropping any one of the premises blocks deriving the contradiction. It would help if you would at least tell me that you understand that.
    TonesInDeepFreeze

    That's one of the contradictions. If one drops or adds or changes any premises, e.g. by stipulating that the lamp spontaneously and without cause turns into a pumpkin at 12:00, then you have resolved the contradiction regarding the state of the lamp at 12:00, but doing so does not then allow for the possibility of supertasks; it does not resolve the contradiction in claiming that an infinite sequence of button pushes has come to an end.

    It is begging the question merely to declare it is a contradiction that denumerably many tasks can be executed in finite time.TonesInDeepFreeze

    It's simply true by definition. An endless sequence of operations cannot end. An infinite sequence of operations is an endless sequence of operations. An infinite sequence of operations cannot end.

    It merely says that metaphysical possibility may be logically possibility and that there's another notion that the article describes ostensively. So is it just the same as logical possibility, and if not what is a proper definition that is not merely ostensive?TonesInDeepFreeze

    I'm not the authority on the matter. I am simply arguing that supertasks are more than just nomologically impossible. I use the phrase "metaphysical impossibility" rather than "logical impossibility" simply because it's the weaker claim. Call it hedging my bets if you will.
  • Infinite Staircase Paradox
    @TonesInDeepFreeze

    As a different example, consider the grandfather paradox. I don't just take this as a proof that one cannot travel back in time and kill one's grandfather before one's father is born; I take this as a proof that one cannot travel back in time.

    The premise of having one kill one's grandfather before one's father is born is just a tool to prove the impossibility, not the reason for the impossibility.
  • Infinite Staircase Paradox
    I didn't say they end.TonesInDeepFreeze

    A supertask is an infinite sequence of operations that ends in finite time.

    Again, the contradiction comes from the conjunction of the premises.TonesInDeepFreeze

    One of the contradictions does; the state of the lamp at 12:00. This isn't the only contradiction. The other contradiction is the inherent contradiction of an endless sequence of operations coming to an end. The former is simply a tool to better demonstrate the latter.

    Finding some way to resolve the former does not also resolve the latter.

    Just in case you missed my edit to my previous post:

    Let's even assume for the sake of argument that this wizard will only appear with a probability of 0.5, and that this is determined only at exactly 12:00, i.e after the performance of the supertask. It must already be possible for the supertask to be performed for him to even appear, and so his appearance cannot retroactively make the supertask possible, even if half the time it resolves the secondary contradiction regarding the state of the lamp at 12:00.

    (3) We don't have a satisfactory definition of 'metaphysical possibility' here.TonesInDeepFreeze

    See here.

    All I mean by it is that supertasks are more than just physically impossible. No alternate physics can allow for them.
  • Infinite Staircase Paradox
    It's not a contradiction in and of itself.TonesInDeepFreeze

    An infinite sequence of operations is by definition an endless sequence of operations. An endless sequence of operations does not come to an end. That's what makes the premise of a supertask an inherent contradiction.

    Having the operation be to push a button, and having this button turn a lamp on and off, is simply a way to make this inherent contradiction even clearer.

    If you accept that this proves that this button cannot have been pushed an infinite number of times then what is the reasoning behind the claim that if some wizard steps in at 12:00 to magically turn the lamp on then this retroactively makes it possible to have pushed this button an infinite number of times? Let's even assume for the sake of argument that this wizard will only appear with a probability of 0.5, and that this is determined only at exactly 12:00, i.e after the performance of the supertask. It must already be possible for the supertask to be performed for him to even appear, and so his appearance cannot retroactively make the supertask possible, even if half the time it resolves the secondary contradiction regarding the state of the lamp at 12:00.

    I don't think you're really grasping what distinguishes a supertask from an abstract infinite sequence.
  • A Case for Moral Anti-realism
    So you think that S can intend that the utterance T will place him under an obligation, and utter T, but not thereby consider themself under an obligation.Banno

    I didn't say that.

    I'm saying that Searle's necessary and sufficient conditions (1)-(9) do not entail that if S promises to do A then S is obliged to do A.

    S can intend that the utterance T will place him under an obligation, and utter T, but not thereby be under an obligation.
  • A Case for Moral Anti-realism
    If "...it isn't clear to (you) what obligations are" and you do not think there are such things as obligations, then you are not going to understand what is involved in making a promise.Banno

    That's why I'm asking you to make sense of them (and then justify their existence).

    As it stands, I am content with accepting Searle's conditions (1) - (6) as being sufficient for promises.

    But also as previously mentioned, not even Searle's conditions (7) and (8) require one to actually be placed under an obligation; they only require that one intends to be. So even under Searle's account obligations are seemingly superfluous.
  • A Case for Moral Anti-realism
    I did indeed promise to answer your question, but I am under no obligation to do so".

    You don't see this as problematic?
    Banno

    No, because it isn't clear to me what obligations are, or whether or not they exist, and you are yet to make sense of them.

    Then I need provide no answer.Banno

    So you will neither make sense of nor defend your claims? OK.
  • A Case for Moral Anti-realism
    So this tells me only that you will not be held to your promises.Banno

    I don't know what it means to be held to a promise. You don't seem to want to make sense of obligations, so maybe you can at least make sense of this?

    OK. You are not a man of your word.Banno

    Whether or not I'm a man of my words depends only on whether or not I actually do as I promise. The existence of some supposed "obligation" or "holding" (whatever they are) is utterly irrelevant, if even sensible.
  • A Case for Moral Anti-realism
    DO you thinkt hat one can sincerely say "I promise to answer you but I will not answer you".

    I'll let you work through it.
    Banno

    No. Where have you derived that conclusion? My issue is with the suggestion that promises entail obligations.

    These are two distinct propositions:

    1. I promise to do this but I won't
    2. I promise to do this but I have no obligation to

    I can't sincerely assert (1) but I can sincerely (especially if I'm a nominalist) assert (2).
  • A Case for Moral Anti-realism
    The linked paper sets out an account that hows how sometimes uttering "I promise to do this" is placing oneself under an obligation.Banno

    Where?

    I can see these closely related conditions:

    7) S intends that the utterance of T will place him under an obligation to do A, and
    8) S intends to produce in H the knowledge that the utterance of T is to count as placing S under an obligation to do A

    These conditions can be satisfied even if the utterance of T does not in fact place S under an obligation to do A, e.g. if obligations do not actually exist. We can intend whatever we like, but the facts do not always accord to our intentions.

    And how does one even justify the claim that (7) and (8) are necessary conditions of promises? Perhaps (1) - (6) are sufficient.

    Of course, this all depends on what being placed under an obligation actually means, as asked above in my previous comments, e.g. are obligations abstract objects of the kind that platonists believe in and nominalists don't? Until this is answered with any clarity it isn't clear what is even being said.
  • A Case for Moral Anti-realism
    More than that. "Promises exist" means that there is an illocutionary act that involves placing oneself under an obligation. Such an act occurs in the world, not in some other domain.

    Not seeing any ambiguity.
    Banno

    The ambiguity is in making sense of the distinction between a) communicating the proposition "I promise to do this" and b) placing oneself under an obligation.

    Do (a) and (b) mean the same thing?

    If so then what is gained in asserting (b) rather than just (a)?

    If not then how do I make sense of (b), especially if I am a nominalist? Is (b) even possible if nominalism is correct? And does (a) necessarily entail (b)? How would such a claim be justified?

    If "promises exist" only means that (a) occurs then I can agree, but if it means that (b) occurs then the issue is unclear.
  • A Case for Moral Anti-realism
    It is a promise, it is an obligation.Banno

    This is an ambiguous claim.

    Are you suggesting that "I promise to do this" means "I am obliged to do this"?
    Are you suggesting that "I promise to do this" entails "I am obliged to do this"?

    Is "I promise to do this but I am not obliged to do this" in some sense a contradiction?

    People make promises. Therefore there are promises. Therefore promises exist.Banno

    This is also an ambiguous claim.

    To say that people make promises is to say that people promise to do something, and to say that people promise to do something is to say that they say something like "I promise to do this".

    Does "promises exist" mean the same thing as "people say something like 'I promise to do this'"?

    Because at least prima facie the former would suggest some sort of platonism/realism regarding the existence of abstract objects whereas the latter wouldn't.
  • Is atheism illogical?
    What possible reason could there be for not allowing for the same possibility with respect to theories about "transcendental entities"?Pantagruel

    Anything that isn't a contradiction is possible. It doesn't then follow that it is not reasonable to believe that some possibilities are true and some are false.

    It is possible that deities exist, but they don't.
  • Is atheism illogical?
    I'm asking you why a narrative that is from the limited human-centric perspective cannot both be inaccurate but also refer to something that in fact exists. Assuming which, yes, the claim that Zeus does not exist (qua "any possible deity") is not logical, that is, is not warranted.Pantagruel

    This is so vague and ambiguous as to be meaningless, i.e. illogical.

    I would say that it is reasonable to believe that Zeus does not exist, that Odin does not exist, that Shiva does not exist, that Allah does not exist, that Yahweh does not exist, and that a supernatural intelligent creator deity does not exist.
  • Is atheism illogical?


    I'm asking what you think. Is it "illogical" for to believe that the Greek, Norse, and Hindu pantheons are a fiction?
  • Is atheism illogical?


    Are these propositions insufficiently justified?

    P1. Zeus does not exist
    P2. Odin does not exist
    P3. Shiva does not exist
    P4. None of the Greek, Norse, or Hindu deities exist
  • Is atheism illogical?


    Then what specifically do you mean by "illogical" if not "contradictory"?

    Do you just mean that the proposition "no deities exist" is insufficiently justified?
  • Is atheism illogical?
    No, atheism is not illogical. The proposition "no deities exist" is not a contradiction.
  • Probability Question
    How could the multiverse be uncountably infinite?RogueAI

    I'm unsure but perhaps:

    For each real number there is a universe in which that number is selected by Michael at random, and the real numbers are uncountable.
  • Infinite Staircase Paradox
    Rather, infinitely divisibility along with the other premises entails a contradiction.TonesInDeepFreeze

    I think this is a misunderstanding of the problem.

    Say we accept that Thomson's lamp entails a contradiction; the lamp can neither be on nor off at 12:00.

    I take this as proof that having pushed a button an infinite number of times is metaphysically impossible.

    You seem to take this as proof that having pushed a button an infinite number of times is metaphysically impossible only if the premises are true.

    As an example, let's say that our button is broken; pushing it never turns the lamp on. In such a scenario we can unproblematically say that the lamp is off at 12:00. But this does not then entail that it is possible to have pushed the button an infinite number of times.

    We can imagine a lamp with two buttons; one that turns it on and off and one that does nothing. Whenever it's possible to push one it's also possible to push the other, and so if it's possible to have pushed the broken button an infinite number of times then it's possible to have pushed the working button an infinite number of times. Given that the latter is false, the former is also false.

    Having pushed a button an infinite number of times is an inherent contradiction, unrelated to what pushing the button does. Having the button turn a lamp on and off, and the lamp therefore being neither on nor off at the end, is only a way to demonstrate the contradiction; it isn't the reason for the contradiction.

    Which is also why Benacerraf's response to the problem misses the mark.

    The pseudocode I provided a month ago helps explain this:

    var isLampOn = false
    
    function pushButton()
    {
      isLampOn = !isLampOn
    }
    
    var i = 120
    
    while (true) {
    
      wait i *= 0.5
      
      pushButton()
    
    }
    
    echo isLampOn
    

    isLampOn is only ever set to true or false (and never unset) but the echo isLampOn line can neither output true nor false. This demonstrates the incoherency in claiming that while (true) { ... } can complete.

    Changing echo isLampOn to echo true does not retroactively make it possible for while (true) { ... } to complete.

    Having pushButton() do nothing does not make it possible for while (true) { ... } to complete.

    It is metaphysically impossible for while (true) { ... } to complete, regardless of what happens before, within, or after, i.e. neither of these can complete:

    Code 1
    var i = 120
    
    while (true) { wait i *= 0.5 }
    

    Code 2
    while (true) { }
    
  • 0.999... = 1
    That makes 0.999999..... = 1 just an illusion created by the notation you have decided to use. It is not a proof. In my opinion. You might have a different idea of what a proof is.Ludwig V

    Well it's not a mathematically rigorous proof as it doesn't prove each of the three steps. A mathematically rigorous proof is much more complex, as seen with TonesInDeepFreeze's answer.

    But it's a simple proof for those that accept each step individually. If you want a proof of these then that's a topic for another discussion, probably on a forum dedicated to maths.
  • 0.999... = 1
    In my book 0.9 + 0.1 = 1 and 1 - 0.1 = 0.9 and so 0.9 does not equal 1. There's a similar argument for 0.99 and 1 and so on. So far each element of 0.99999....., I have an argument that it does not equal 1. However, I see that your proof involves limits and I know that in that context words change their meanings. So I'm curious.Ludwig V



    Let's not distract from supertasks by questioning very simple mathematical facts.
  • Infinite Staircase Paradox


    That comment was directed at fishfry who claims that the lamp can turn into a pumpkin or spontaneously and without cause be on at 12:00.
  • Infinite Staircase Paradox
    Thomson’s lamp revisited makes much the same points I have made:

    P13 Some infinitist claim, however, that at tb, after performing Thomson’s supertask, the lamp could be in any unknown state, even in an exotic one. But a lamp that can be in an unknown state is not a Thomson’s lamp: the only possible states of a Thomson’s lamp are on and off. No other alternative is possible without arbitrarily violating the formal legitimate definition of Thomson’s lamp. And we presume no formal theory is authorized to violate arbitrarily a formal definition, nor, obviously to change, in the same arbitrary terms, the nature of the world (Principle of invariance). It goes without saying that if that were the case any thing could be expected from that theory, because the case could be applied to any other argument.

    i.e. the lamp can't turn into a pumpkin.

    P16 At this point some infinitists claim the lamp could be at Sb by reasons unknown. But, once again, that claim violates the definition of the lamp: the state of a Thomson’s lamp changes exclusively by pressing down its button, by clicking its button. So a lamp that changes its state by reasons unknown is not, by definition, a Thomson’s lamp (Principles of Invariance and of Autonomy).

    i.e. the lamp is on if and only if the button is pushed (when the lamp is off) to turn it on (and not then pushed to turn it off).
  • Infinite Staircase Paradox
    Next would be to examine whether your inference is correct that the problem shows that time is not infinitely divisibleTonesInDeepFreeze

    The simple reasoning is that if time is infinitely divisible then pushing a button an infinite number of times within two minutes is theoretically possible. Pushing a button an infinite number of times within two minutes entails a contradiction and so isn't theoretically possible. Therefore, time is not infinitely divisible.

    Although I think perhaps this variation of Zeno's paradox might be better at questioning the infinite divisibility of spacetime.
  • Gödel's ontological proof of God


    I think you've misunderstood these:

    1. ◇∃x(F(x) ∧ A(x))
    2. ◇∃x(F(x) ∧ ¬A(x))

    They say:

    1. It is possible that there exists some X such that X is the only unicorn and is male
    2. It is possible that there exists some X such that X is the only unicorn and is not male

    They are not inferences but independent premises and might both be true.

    My argument is that we cannot then infer these:

    3. ◇□∃x(F(x) ∧ A(x))
    4. ◇□∃x(F(x) ∧ ¬A(x))

    Which say:

    3. It is possibly necessary that there exists some X such that X is the only unicorn and is male
    4. It is possibly necessary that there exists some X such that X is the only unicorn and is not male

    Under S5 they cannot both be true.

    This matters to modal ontological arguments because (3) and (4) are equivalent to the below:

    3. It is possible that there exists some X such that X is the only unicorn and is male and necessarily exists
    4. It is possible that there exists some X such that X is the only unicorn and is not male and necessarily exists

    The switch from "possibly necessary that there exists some X" to "possible that there exists some X such that X necessarily exists" is a sleight of hand. It is used to disguise the fact that asserting the possible existence of God – where necessary existence is a property of God – begs the question.
  • Gödel's ontological proof of God
    Cool. Well if it helps, I've re-written that first comment to correct the typos and to hopefully be clearer.
  • Gödel's ontological proof of God
    I hope it won't be too long that I'll have time to resume going over your argument with the emendations.TonesInDeepFreeze

    Are you waiting on me for something else or are you saying that you're currently too busy to examine what I've said?
  • Gödel's ontological proof of God
    Also, you have a modal operator after a quantifier.TonesInDeepFreeze

    Yes, good catch. I should have used ◇□∃xP(x).

    Am I correct that by "we cannot assume pEx(nPx) is true for any logically consistent Px" you mean "For all consistent Px, we have that pEx(nPx) is not logically true"?TonesInDeepFreeze

    What I am saying is that ◊∃xP(x) ⊬ ◊□∃xP(x), i.e "it is possible that X exists" does not entail "it is possibly necessary that X exists".
  • Infinite Staircase Paradox
    When you say "there are no spontaneous, uncaused events," you are ignoring the physically impossible premises of the problem.fishfry

    No I'm not. I accept that one of the premises of the thought experiment is physically impossible. That doesn't then mean that we cannot have another premise such as "there are no spontaneous, uncaused events".

    You seem to think that because we allow for one physical impossibility then anything goes. That is not how thought experiments work.

    It is physically impossible for me to push a button 10100100 times within one minute, but given the premises of the thought experiment it deductively follows that the lamp will be off after doing so. Your claim that the lamp can turn into a plate of spaghetti is incorrect.
  • Gödel's ontological proof of God
    It would help if you would give one self-contained argument with transparent inferences from start to finish.TonesInDeepFreeze

    I think the previous argument did that? Perhaps you could let me know which line(s) you'd like me to explain further?
  • Gödel's ontological proof of God


    The explanation of the argument here presents the problem more clearly.
  • Infinite Staircase Paradox
    I want to get back to looking at this more closely, but in the meantime, do you consider your presentation equivalent with Thomson's statement of the problem?TonesInDeepFreeze

    Yes.