So now we're back to Isaac's teapot and the missing screw. In that discussion, the question was only about successfully referring to a particular that (might or) might not possess a property you believe (or don't believe) it does. I think it's plain that you can; for some cases, I'm leaning on the causal theory of names, and for others on how demonstratives work: you can clearly demand someone get "that" off your kitchen table even when you know very little about what "that" is. Exactly how that works may be unclear; that it works, I believe, is not. (We may come back to the double-bind theory of reference eventually.) — Srap Tasmaner
Here, we might start with the question of whether "being on my kitchen table" is a property of the object in question. It can be expressed as a predicate, as I've just done, but we could just as well express the situation as my kitchen table having the property of "having that on it," assuming again that "that" will manage to refer to the object. Or we could define a two-place predicate "on" such that "on" is true of an ordered pair <that, my kitchen table>. For either of the one-place predicates (of that, or of the table), I would be asking you to make something that is true of one of them false; for the two-place predicate, I would be asking you to make something that is true of the two of them false. — Srap Tasmaner
Do we say that "on" takes three objects, the two from before and a third that specifies the order? If so, the third would look something like this: "1 = thing, 2 = table". Such a list can be presented in any order, so we don't have a regress, only a rule about each natural number up to the arity of the predicate being used, so this is a genuine option. But our new on/3 takes two concrete objects and a third which, whatever it is, is not like that. I say "whatever it is," because the semantics of the ordering list are unclear at this point: are those objects in the list, or expressions referring to objects? I guess either would do, but we're still building in a lot of other stuff, some of which looks suspiciously abstract, so we could just give in and have "on" take a single abstract object which is the ordered pair <thing, table>. — Srap Tasmaner
Can we do something similar with other cases? For instance, if my bike tire is flat, is it a different object once it's inflated, or is it just a different arrangement of tire and air, the tire itself never changing? (In this case, we may or may not have any specific batch of air in mind.) But then what would we say about the shape of the tire, that surely changes when it's inflated? If anything is a property of an object, surely its shape is. But I make different shapes when I sit and when I stand — does that make me a different person? What all of these examples have in common is that there are at least two different times considered: the tire is never flat and inflated at the same time, I am never sitting and standing at the same time, and so on. So a first attempt at distinguishing what is essential to an object from what is accidental is, naturally, distinguishing what is constant or invariant about it, what does not change from one time to another, and what does or can change from one time to another. Essential is what is time-less, and accidental is what is time-dependent. The same dog barks at one time and not at another. — Srap Tasmaner
One solution offered, in a sort of conventionalist spirit, is that this is all a collective fiction: there are no things with identities that we come along afterward and refer to; rather, our various acts of reference, intended and accepted by us as such, and our deeming these acts successful, is all there really is here. — Srap Tasmaner
That means there are two overlapping arguments here: one the one hand, the conventionalist can keep poking holes in whatever theory of object identity the other side comes up, because he needs no such theory anyway, and may even think no such theory is possible; on the other hand, the object-identitarian has to come up with a theory that works and show that it is needed, which means he also has to find some flaw in the conventionalist account of our referential speech acts — not for the sake of his theory but to show that some theory is even needed. What's not clear in any of this is how the evidence is to be handled: I'll venture that most people's pre-theoretical intuition is that we talk the way we do because things are the way they are, and that our talking the way we do is in fact evidence that things are the way we say they are.
But we have those pesky scientific refutations of how we talk: sunrise, solidity, and so on. That doesn't show that how we talk is never evidence of how things are, but it does show that it isn't always such evidence. On the other hand, the conventionalist can shift from the claim that how we talk is only evidence of how we talk, and nothing more only for methodological reasons, to a claim that how we talk is only we how talk — now meaning our agreement is precisely evidence that there is nothing more. — Srap Tasmaner
If that were true, it would not only deny the object-identitarian what was counted pre-theoretically as evidence but change the character of what's to be explained by any such theory. If the mean girls call you a loser, that's just a thing they say: the truth-value of their statement matters to you, but not to them; what matters to them is producing some effect, of hurting your feelings. That's the sense in which it is "just something they say." But not only can you not conclude from someone saying something that it must not have a truth-value, in this case the effect is only produced if you assume that it does, and they assume that you will assume that it does. If they know you will discount what they say as being just mean-girl noise, or just noise period, there's no reason for them to say it. The conventionalist can retreat again and say that the hurt feelings are known inductively to follow utterances of "loser," and that's all the mean girls need. That might actually be true! But you have to show that such an account really will extend to cover all language use. This situation is so simple than I think what we're really seeing is not exactly language at all but something more like dominance signaling that happens to use language because, well, there it is; we tend to use words even when what we're doing is really nothing more than growling articulately. — Srap Tasmaner
If the entire linguistic community agrees that this ball is "red", then how might our "reasoning" be wrong? What "reasoning" is involved when we teach someone how to use the word "red"? — Luke
Is this ball *this ball* if it is a different color? Is redness essential to it? For comparison, if this ball is flat, we can inflate it, and we will not usually say that being flat is essential to what the ball is, just its temporary state. — Srap Tasmaner
When talking about particulars, like this specific ball, we can't make modal claims, I think, without considering what is essential and what accidental about that particular. — Srap Tasmaner
But it is nevertheless true that if it is flat, it is not fully inflated, and that's just the law of noncontradiction. When we say this red ball cannot not be red, are we even saying anything about the ball? Or are we only saying that at this world, as at all others, the law of noncontradiction holds? — Srap Tasmaner
To say that there are no worlds at which this ball is both red and not red is to say almost nothing at all. There simply are no such worlds, no worlds at which any ball, this one or another, is both red and not red. If we deem the redness of this ball essential to it, there are no worlds at which this ball is not red, on pain of simply being a different object. If it is inessential that it is red, like being flat, then there are worlds at which it is blue, is green, is white, and so on. And that's what we mean when we say this ball 'might have been' some other color. — Srap Tasmaner
We're in very different territory if there's a bin of red playground balls and you're grabbing one of those. In such a case, it's perfectly clear what we mean when we say you cannot pick a ball that is not red: there is no such a ball to pick. To say that you might get the one with "Zeppelin rules" scrawled on it in Sharpie, is to say there is a ball in the bin so adorned, and this inscription makes it unique; to say you might get one bearing those words, is to say this is a thing someone might have done, that it is possible someone has done it. — Srap Tasmaner
But how do we get necessity out of the law of noncontradiction? That if something is red, it cannot not be red? Since the law of noncontradiction holds at each world, restricting to worlds at which "The ball is red" is true automatically embodies the necessity we were looking for: for any world w in that set, the ball is red at every world accessible (under this restriction) from w. That's our definition of necessity. No world at which it is not red, or also not red, can sneak in. — Srap Tasmaner
You say a lot of things I agree with, but apparently thinking that I don't, because there's still some confusion about the handling of "not." One point I think I clarified somewhere else is that in something like "The book is not red," we place the "not" before "red" purely as a matter of English convention, and because, with no other scope in play, there's no ambiguity. But that's still a proposition-level "not" and a more verbose way to say the same thing is "It is not the case that ball is red." It's sometimes convenient to pretend that "not red" is something we might predicate of an object, but it isn't really. "Not red" is not a syntactical element of the proposition at all, and therefore not a semantic unit either. "Red" is, as a predicate, and "not" is, as an operator on the entire proposition. "Not" doesn't apply to predicates or objects. As long as we keep in mind the logical form of what we're saying, I see no harm in using ordinary English, but I'll switch to "philosophical English" when there's ambiguity to be avoided. — Srap Tasmaner
You are making what I would consider a scope error. — Srap Tasmaner
(1) It is necessary that the book falls if and only if it is not possible that the book does not fall.
(2) It is possible that the book falls if and only if it is not necessary that the book does not fall.
"Not" seems to be used in two ways, but it really isn't; under this scheme it is always a proposition-level operator, just like "possibly" and "necessarily". You build necessary this way:
(1) The book is falling.
(2) It is not the case that (1), the book is falling.
(3) It is possible that (2), that it is not the case that (1), the book is falling.
(4) It is not the case that (3), that it is possible that (2), that it is not the case that (1), the book is falling.
(5) It is necessary that (1), the book is falling.
(5) is here just shorthand for (4). There is a single complete proposition (1), and three operators applied to that proposition, which we can abbreviate as a single operator.
This simplified usage of "not" avoids many confusions: you never predicate "not falling" of an object, you deny that it is falling; you never predicate "not possible" of a proposition, you deny that it is possible. By maintaining discipline in the treatment of "not", you avoid any possibility of confusing, say, "I know it's not Tuesday" and "I don't know it's Tuesday". We can be clear about the scope of the operators we apply to sentences, and we can be clear about the order in which we apply them, and we need not abide ambiguity. This is how we win. — Srap Tasmaner
Metaphysically speaking, I take these terms to mean:
1. Impossible = cannot occur
2. Possible = can occur
3. Necessary = must occur
This does not make "necessary" and "possible" the same. It opposes the concepts of 1 and 2 to each other, and the concepts of 2 and 3 to each other. This does not require "possible" to be in a distinct category. — Luke
You are making what I would consider a scope error. — Srap Tasmaner
(2) It is possible that the book falls if and only if it is not necessary that the book does not fall. — Srap Tasmaner
There are only two feelings, pain and pleasure, each with varying degree. — Mww
Whether or not all that is granted, it nonetheless authorizes us to say judgements are limited as constituents of our moral disposition, in that because we are this kind of moral agent we will judge good and bad in this way. — Mww
Now, again, best to keep in mind this kind of judgement is aesthetic, representing a feeling, as opposed to discursive, which represents a cognition. We often do good things that feel bad, as well as do bad things that feel good. From that it follows that the judgement of how it feels subjectively to do something, is very different than the judgement for what objectively is to be done. — Mww
Simple example of how we do this, instead of all this concept juggling:
(1) It is necessary that the book falls if and only if it is not possible that the book does not fall.
(2) It is possible that the book falls if and only if it is not necessary that the book does not fall.
"Not" seems to be used in two ways, but it really isn't; under this scheme it is always a proposition-level operator, just like "possibly" and "necessarily". You build necessary this way: — Srap Tasmaner
I agree. — creativesoul
If it isn't clear, the interdefinability of such operators means you only need one of them, but using the pair is way more convenient, and foregrounds how common and important two particular ways of using such an operator are. In other words, we could get by with just ▢ for a modal operator, and we would find ourselves writing formulas with ▢~, and ~▢, as well as unadorned ▢, but we would also find that we were writing one particular little phrase all the time: ~▢~. Same is true for ∀ and ∃: if we just used ∀, we'd have to write ~∀~ all the time. — Srap Tasmaner
We have to be able to say that what is cannot not be without falling into a modal fallacy of treating all truths as necessary. — Srap Tasmaner
I’m pretty sure I’m not committing that fallacy, but I can see how MU most likely is. — Luke
Best to recognize that I cannot reject that this is a bus when I already have experience of busses, which manifests as a blatant self-contradiction, in just the same way I cannot reject the feeling of moral reprehensibility, but without ever having the experience of an object by which a self-contradiction would arise. This is sufficient to prove feelings are not cognitions, from which follows that moral knowledge is a misnomer. Further support resides in the fact that I may know this is true now yet find later this is no longer known as true, a function of experience in which I must cognize something, but that for which I feel as moral will always be what I feel is moral, as a function of personality, for which no cognitions are necessary. — Mww
we should find that it is impossible to be dishonest with oneself. — Mww
Nobody but you uses "necessary" to mean "no longer possible". — Luke
This fails to answer whether the original event was necessary or merely possible in the first place. — Luke
Whoa! Do I get some sort of prize for bringing this about? — Srap Tasmaner
And that's not crazy: counterfactual reasoning is famously dicey; but it is just as famously indispensable — Srap Tasmaner
Or, consider this: we don't actually act upon the future directly either; that too, we are incapable of doing. We can only act in the present to select which possible future is realized. But every time we do that, we are also, immediately, filling the past with events of our choosing. The past is what we have some say-so in, never the future. — Srap Tasmaner
Now you also agree that it's only events of the past that are immutable in this way, right? Events in the future are not only not immutable, they're not even fully determined; and the present, well, the present is presumably the moment of an event being fully determined and thereby becoming immutable. — Srap Tasmaner
And all of this is still circling around the problem of truth, because the past is the paradigmatic realm of truth, eternal and unchanging, while there is no truth about the future and for that reason no knowledge but only belief. — Srap Tasmaner
Seems an awful lot like the same thing, doesn’t it? — Mww
Same point as just the innate capacity for empirical knowledge doesn’t contain any. — Mww
Truth, as such, is every bit as subjective as one’s moral disposition and experiences. — Mww
That does not explain why present/past situations are necessary; or why it is necessary that I had to have toast instead of cereal for breakfast this morning. — Luke
I am resisting your "proposal" because if we have a real choice in the matter, like you say we do, then it was not necessary that I had toast instead of cereal for breakfast this morning. I had a real choice to have had cereal instead of toast. That is, the past situation of me having toast for breakfast this morning was not necessary. I am using "necessary" here in the sense of "inevitable" or "predetermined", as opposed to having a "real choice" in the matter — Luke
We believe we can make a distinction between events that were bound to happen, and events that were not; in which case, there must be a difference between (1) saying, at a time B or later, that nothing can happen that will make it so that the coffee has not fallen, and (2) saying at a time A or earlier, nothing can happen that will make it so that the coffee does not fall. To say that an event in the past was not inevitable, is to say that (1) is true of it but (2) false. — Srap Tasmaner
Is there any non-question-begging way to deny this is possible? We cannot, ex hypothesi, object that an event in the past at time X is in the past for any time after X; the hypothesis is exactly that this is not so. In what, then, does the immutability of the past consist? Is it brute fact? Could it conceivably not be? — Srap Tasmaner
f it was ever possible to prevent the cup of coffee from falling off the car, then at no time is it, was it, or will it be necessary or inevitable that it did fall. — Luke
That being said, I agree moral rules are much more important than conventional rules, but that alone says nothing with respect to their logical ground..... — Mww
If it should be the case that the human intellectual system, in whichever metaphysical form deemed sufficient for it, is entirely predicated on relations, it should then be tacitly understands that system is a logically grounded system, insofar as logic itself is the fundamental procedure for the determination of relations. Hence it follows, it being given that all rules are schemata of the human intellectual system, and the human intellect is relational, then all rules are relational constructs. From there, it’s a short hop to the truth that, if all rules are relational, and all relations are logically constructed, and all logical constructs themselves are determinations of a fundamental procedure, then all rules are logical rules. — Mww
Logical principles are neither moral nor immoral. Morality is an innate human condition, determinable by logical principles which relate a purely subjective desire to an equally subjective inclination. In other words, this feels right, therefore it is the right thing to do and I shall will an act in accordance with it. — Mww
For example, if I had a real choice of whether to have toast or cereal for breakfast this morning, then it was not necessary that I had toast (as I did) because I could have had cereal instead. — Luke
If the former, then what is actual is/was not necessary. — Luke
You refuse to acknowledge this argument against the necessity of actuality. — Luke
Is it the same to say logical rules are useful in support of the attainment of personal goals? — Mww
If the most personal one can be, is demonstrated by his moral convictions, and if logical rules are the ground for particular personal goals, then it follows that logical rules are not so much merely consistent with, as in fact necessary for, the dispensation of him toward his moral activities. — Mww
All rules developed and used by us, in private, rational decision-making, re: judgment, without exception, are reducible to logical rules. — Mww
I'm pointing at that phenomenon so that I can block it from undermining our claim that actuality entails possibility. If it's only a conversational implicature, it has no bearing on the relevant entailments. — Srap Tasmaner
Are they real possibilities which each have a genuine chance of being the actual outcome, or are they merely a function of our knowledge/ignorance and there is only ever one real possibility? — Luke
If the former, then what is actual is/was not necessary. If the latter, then we have no free will. — Luke
As I said, the possibilities which are present, at the current time (at t0), are possibilities regarding the future situation (at t1). You acknowledge this with the example about today's possibility of tomorrow's sea battle - the possibilities are regarding the future situation, not the present situation. The possibilities are not about themselves; they are about the future potential sea battle. — Luke
And I am saying that if there were other genuine possibilities prior to the act being carried out, then it was not necessary, because one of those alternative possibilities could actually have been carried out instead. It is only if there had been no other genuine possibilities that could actually have been carried out instead, that the act being carried out would be necessary. — Luke
Your assertion that all actual situations are necessary negates that there are ever any genuinely alternative possibilities, and thus precludes free will. — Luke
No, the speaker might know that the book is in the car but choose to be coy, though literally honest and correct, in saying "The book might be in the car". If I was looking for the book, then I would not appreciate my friend being coy that way, but he would not be logically incorrect. — TonesInDeepFreeze
You are talking with a poster not capable of making sense. — TonesInDeepFreeze
The sad thing is that your clear explanation will not correct the confusion here. That confusion is wilful. — Banno
Those different possibilities are regarding a future situation, not the current situation. — Luke
For example, the hypothetical assumption “Suppose I have lost my copy of Lewis 1973” picks out a set of possible worlds at which I have indeed lost my copy of Lewis 1973. If I determine that in any such world (or only in nearby worlds, or in sufficiently similar worlds, etc., whatever the appropriate restriction is) I would be a miserable cuss, and I would prefer not to be, then I can discharge the assumption by concluding, for example, “If I were to lose my copy of Lewis 1973, I would have to replace it.” — Srap Tasmaner
We do not know whether there will be a sea battle tomorrow, and it is possible today that there will be a sea battle tomorrow or there won't be a sea battle tomorrow. But. come tomorrow, there will be no other possibilities regarding the sea battle except for the one that becomes the actual situation. — Luke
Exactly. The particular possibilities at t0 are possibilities regarding the future situation at t1; they are not possibilities regarding the present situation at t0. There are no other possibilities (for t0) at t0 other than the actual situation. — Luke
ou either had other possibilities (prior to eating the cake) at t0 besides eating the cake at t1, or you didn't have other possibilities at t0 besides eating the cake at t1. If you had other possibilities at t0, then eating the cake at t1 was possible. If you didn't have other possibilities at t0, then eating the cake at t1 was necessary. I don't agree that eating the cake at t1 was necessary if you had other possibilities at t0. This a misuse of the term "necessary". — Luke
You appear to be equivocating on the meaning of "means". We're using it in the sense of a definition, not in the sense of entailment. — Michael
The T-schema doesn't say that asserting the proposition "the book is in my room" entails that the book is in my room. It only says that the book being in my room is the truth-condition of the proposition "the book is in my room", and according to Davidson the definition of a proposition is given by its truth-conditions. — Michael
What you mean by "possible" is that the future holds more than one possibility; that there are several possible worlds and one of those becomes the actual world. — Luke
If there is more than one possible world at t0 and one of those becomes the actual world at t1, then the actual world at t1 is still one of those possible worlds that was at t0; one of the possibilities that could have been. — Luke
If you had many possibilities prior to the act, then the one that became actual remains one of those possibilities. — Luke
Ok. What is communion as you’re using the word? — Mww
That I can assert a falsehood isn't that it doesn't mean precisely what it says. — Michael
No, I don't. It's a nonsensical inference. — Michael
The meaning of "the book is in my room" doesn't concern what I believe. — Michael
It is not the case that (1) entails (2). It just doesn't. But conversationally, we take an utterance of (1) to implicate a commitment to (2). And that commitment is purely conversational; you do not contradict yourself if you say, "Well, it might be in my room — as a matter of fact I know that it is." — Srap Tasmaner
There's no more a contradiction here than there is in Mitch Hedberg's joke, "I used to do drugs. I still do, but I used to too." Implicature is not entailment; that's the whole point. — Srap Tasmaner
And that's another reason that approaching all philosophical problems in terms of what people say or can't say is so misleading; there are other rules than logic at work in what people say to each other and what it will be taken to mean. — Srap Tasmaner
"Possible" is the opposite of "impossible". It is absurd to deny it. — Luke
You do not get to personally decide the meanings of these words. — Luke
Whether or not the book is actually in my room has nothing to do with what I believe. — Michael
No it isn't. It's the only thing that's relevant. We're concerned with truth, not belief. Your mistake is to continue to treat the word "true" as meaning "honest", which it doesn't. — Michael
The book doesn't just cease to exist, or fail to have a location, simply because I don't know where it is. — Michael
Interesting. What other rules might those be? — Mww
But I'm not implying that the book isn't actually in my room. — Michael
However, if I recall correctly, you made the absurd claim earlier that "possible" is not the opposite of "impossible". — Luke
Then you have likewise rendered "possible" as extremely ambiguous and misleading. — Luke
This thread's going swimmingly. — Banno
But to say that the future is as yet undetermined, for instance, or that we cannot change the past, if those are to be substantive claims, have to mean something besides the future is future and the past is past. What underwrites that understanding of the temporal modalities? — Srap Tasmaner
I think we can say more, and the way to say more is to turn to mathematics, from which time has been deliberately excluded. See what you still have without time. What we find is that there are ways to make issues we are familiar with most often in temporal terms tractable for reason in non-temporal terms. — Srap Tasmaner
I would have thought the opposite to "may or may not be" was "must or must not be". — Luke
If what is actual is not (also) what is possible, then what is actual is (also) what is necessary.
If what is actual is (also) what is necessary, then this precludes free will. — Luke
Clearly this is opposed to common use. — Michael
What’s incoherent in the successive accumulation of the real? When the accumulation is the content of the possible, the quantity is irrelevant. It is whatever it is. — Mww
Agreed. That in quotation marks and taken from my comment, indicates I said it. But I didn’t. I said that which exists is in the sum of the possible. — Mww
So what's the difference between "not actual" and "non-actual"? — Michael
That aside, either if something is possible then it isn't actual or something can be both possible and actual. So which is it? — Michael
Kant says no....That which exists is in the sum of the possible. The sum of the real, the actual, cannot exceed the sum of the possible, therefore is contained by it. — Mww
You asserted the latter, which is false. — Michael
This is false. That the book is possibly in my room isn't that the book isn't actually in my room. — Michael
When I say "the book is possibly in my room" I'm not saying "the book isn't actually in my room". — Michael
Otherwise telling you where something might be is telling you where not to look.
Your position doesn't appear consistent with common use. — Michael
I use a different definition, but the ends are the same. Possibility is merely one of the ways to think about things; a thing is possible or that thing is impossible, but that does not make the conceptions themselves opposites. All they do is condition the thought of the thing. Just as cause is not the opposite of effect; just as necessary is not the opposite of contingent. — Mww
As a temporal sort of modality, that seems fine. Once I have marked a box, would either of you say that it is true of each of the other boxes that, though it is not the box I marked, it might have been the one that I marked? If actuality is the closing off possible futures, can we not imaginatively consider an early time at which the actual present was only a possible future, one among many? — Srap Tasmaner
Above I spoke hypothetically of having a stack of boxes one of which I intended to mark. How do you conceptualize what we are doing when we reason in this way? Am I talking about a possible future in which I do have a stack of boxes? — Srap Tasmaner
Yes, I was. But I can adapt to your usage. All I need to say, using your terminology, is that the actual world is a world. Done. In my usage, if the actual world is not a member of the class of possible worlds, it’s a member of the complement, which would be the class of impossible worlds — if there are any such things, depending on the accessibility relation. — Srap Tasmaner
An assumption H, for the purposes of hypothetical reasoning, picks out a set of worlds at which H is true. The actual world may be such a world. — Srap Tasmaner
All good? — Srap Tasmaner
In modal logic, p → ◇p. If something is true then it is possibly true. Possibility is defined as "not necessary", and something is necessary if it is true in all possible worlds. — Michael
Fine. It’s not my usual usage, but if you want to reserve possible for non-actual, it makes no real difference. It makes world carry a little more of the burden, but that’s also fine. — Srap Tasmaner
Not *only* the same, because it's the one with the x on it, but it's still a box. You forgot to give an argument that putting an x on a box makes it not a box, or that you have to erase "possible" in order to write "actual". — Srap Tasmaner
What's odd here is that the complement of possible is impossible. Me, I assumed actuality implied possibility. I'm puzzled why you think actuality implies impossibility. — Srap Tasmaner
We don't know with deductive certainty. But that's not the relevant or appropriate standard. The relevant standard is to look out the window and see whether it's raining. — Andrew M
So if I have a stack of boxes and put an X on one of them with a Sharpie, it’s no longer a box. Cool. Nice job. — Srap Tasmaner
An assumption H for the purposes of hypothetical reasoning picks out a set of possible worlds at which H is true. That set may or may not include the actual world. We may or may not know whether it does. — Srap Tasmaner
The goal then would be to discharge the hypothetical assumption in a true counterfactual conditional, which may be degenerate in the sense of having an antecedent that is true at the actual world. I understand those are tricky to deal with, but oh well. — Srap Tasmaner
For example, the hypothetical assumption “Suppose I have lost my copy of Lewis 1973” picks out a set of possible worlds at which I have indeed lost my copy of Lewis 1973. If I determine that in any such world (or only in nearby worlds, or in sufficiently similar worlds, etc., whatever the appropriate restriction is) I would be a miserable cuss, and I would prefer not to be, then I can discharge the assumption by concluding, for example, “If I were to lose my copy of Lewis 1973, I would have to replace it.” — Srap Tasmaner
Obviously it is an assumption of the hypothetical that it is raining. But Alice makes no such assumption. She instead forms the justified belief that it is raining because she looked out the window and saw what looked to her to be rain. (Or, for Srap Tasmaner: in knowledge-first terms, Alice knew that it was raining because she looked out the window and saw that it was raining.) — Andrew M
Yes, of course. What the hypothetical shows is that knowledge is possible on a JTB view. Alice's belief was justifiable in both hypotheticals even though there was the possibility (from her point of view) that she could be mistaken (as she was in the second hypothetical). — Andrew M
BTW, as a general observation, you and I are, in effect, speaking in two different languages. What makes it especially difficult to translate is that we use the same words to convey very different ideas, such as "know" (which is ordinarily used in a factive sense), "true", "assumption" and I suspect a few others. — Andrew M
Still not sure what point you’re making though. — Srap Tasmaner
Perhaps the assertion "I know that p" is implicitly the assertion "I know that p and I am certain" and so the assertion "I know that p but I am not certain" is implicitly the contradictory assertion "I know that p and I am certain but I am not certain"? — Michael
No, the hypothetical shows the logical consequences which follow from the condition that it is actually raining in the real world. People make assumptions. But whether it is raining or not is a condition that is independent of people's assumptions. — Andrew M
I for one would appreciate it if you stopped saying things like this. Andrew and Michael are clearly not trying to deceive you. If they are mistaken, then they are mistaken, but there’s no deception here. — Srap Tasmaner
(2) If, for the sake of a hypothetical bit of reasoning, and with some concern about the weather but no access at the moment to a weather report, suggest that if it is raining, we won’t be able to go for a walk, I hold no belief either way about whether it is raining; I only mean to suggest how we should act if it turns out (that is, if at a later time we actually know) that it’s raining. Quite different from (1), in which the “assumption” is what I honestly believe. That’s simply not the case here. NB: these are the sort of assumptions that must be discharged; it’s just the terminology of natural deduction. — Srap Tasmaner
You may of course do as you like, but the rest of us have not invented some special usage for “know” or for “true”; I’m using them exactly the way everyone I know uses them, this being the population that is also perfectly comfortable saying “I could have sworn I knew where I left it, but it’s not there, so I guess I was wrong.” — Srap Tasmaner
Here, I’ll give you a good one. When I was a kid, I was taught, and I learned, that there are nine planets. That is no longer true, but it was true at the time, because there is a specific body of astronomers who make the “official” determination of whether a solar object is a planet. In such a case, I might be able to say I used to know that there were 9 planets, but now I know that there are 8. Note that I have made no mistake and have no reason to retract my knowledge claim. But suppose it was a couple weeks before I heard that Pluto had been demoted; during that time I might get into a heated argument with someone I think a fool because he says there are only 8 planets. At this point I will be wrong; I will be in the position of thinking that I know how many planets there are, and I will be wrong about that. Once he points out to me that there was a change in Pluto’s status, I will readily admit that I thought I knew, but that he was right. — Srap Tasmaner
