Well put. It’s nice to have a place to practice philosophy (to some extent) as opposed to just telling someone what views are out there.

I suppose you don’t consider doing the dishes a real accomplishment? I guess I have lowered my expectations with age.

In the (or a) knowledge version of the surprise quiz paradox, we ask whether the student can know there will be a surprise during a certain finite period. Suppose the student knows at the outset (Monday). Suppose he then knows at the end of Thursday that there’s been no quiz. Can we then rule out Friday as a quiz day by deducing that the student knows there’ll be a quiz Friday?

The critical question is what the student knows on Thursday. Does the student know everything he knew on Monday? If just some, what specifically does he know?

The argument is alluring because we have just supposed the student knows various things on Monday. There’s probably some convention about hypotheticals that if you suppose an aspect of the setup it remains supposed. So the argument assumes that at the end of Thursday it remains supposed that the student knows there’ll be a surprise quiz this week.

Supposing the student knows on Thursday there’ll be a surprise quiz this week, and none has happened, it does follow that the student knows there’ll be a quiz on Friday. But it also follows that the student doesn’t know there’ll be a quiz Friday. Since the student knows the quiz will be a surprise, and knowledge that P entails P, it follows that the quiz will be a surprise. So a contradiction follows: the student knows there’ll be a quiz and not-(the student knows there’ll be a quiz).

That’s no skin off the student’s back. He’s trying to show knowledge of a surprise quiz is impossible. Deriving a contradiction from a supposition is a great way to way to show the supposition is false.

But the real lesson is that we’ve granted the student too much. It is a convention of made up situations that if they are made up some way, they remain made up that way. But there’s no requirement that suppositions remain constant. We just can’t add the supposition that the student knows there has been no quiz by Thursday to the supposition that he knows there’ll be a surprise quiz. The student can’t know all of that. The student can’t know [(there’ll be a quiz this week) & there hasn’t been a quiz by Thursday & I don’t know in advance the day the quiz will happen on].

Just b/c it’s possible to know there’ll be a surprise quiz on Monday, it doesn’t follow that it’s also possible to know there’s a surprise quiz etc. on Thursday.

Kripke says you tweak the scenario so that the student knows axiomatically that there’ll be a quiz. In that way he knows some of what he knew Monday, but not all. He knows the important part from the perspective of inferring that he knows there’ll be a quiz on Friday. He knows there’ll be a quiz this week. So then he knows there’ll be a quiz Friday.

Why should we care about this setup? What seemed intriguing to many of us was the possibility of proving lack of knowledge with a setup that more or less tracks life.

There’s all kind of a double negative question, but there are people who don’t ask the question what is the meaning of life. Tons

Chill?

Thanks for the clarification.

Seems like the surprise quiz paradox isn’t unique in illustrating the flaws of formal logic from your perspective. So ideally one would bracket those in thinking about the SQP. Perhaps the paradox isn’t so paradoxical for independent reasons.

On the kk situation, I’m thinking maybe the student doesn’t know on day 4 that he knew on day 1. I feel totally fine resisting the inference that his knowledge has to survive the change in circumstances. Why shouldn’t it be similarly unlikely that his knowledge of knowledge survives? As the student thinks about things at the end of day 4, the argument has given little assurance that he’ll know that he knew. He should think on day 4, “huh, maybe I never knew.”

One way to think of this is that the student knows that he knows in general. If he knows p at t then he knows that he knows p at t. That’s probably an assumption the student needs. And his kk knowledge is no more guaranteed to survive the changing circumstances than his knowledge.

As a fan of logic, rejecting logic isn’t an option for me.

Suppose we don’t assume anything about anyone’s knowledge on day 1. And suppose, as is usually the case, that we’re considering proving a surprise quiz is impossible. Then it surely does not follow that a surprise quiz can’t happen on day 5.

The argument is supposed to go that at the end of day 4, the student knows there’ll be a quiz on day 5. But he has no idea really. We didn’t build him having knowledge into the setup at day 1 and therefore he won’t magically have knowledge at day 4. The assertion that he does have knowledge at that point is totally unsupported.

So of course if we don’t assume anything about the student’s knowledge in the setup there could be a surprise quiz on day 5. Day 5 comes; a quiz happens; and the ignorant student says - “wow, I didn’t see that coming.”

Philosophy is the investigation of fundamental aspects of reality.

What is the ego death of humanity?

Welcome to philosophy!! It’s wonderful spiritually even if not financially :-)

The teacher in the surprise quiz paradox announces on day 1 that there will be a surprise quiz this week, which has 5 days. The paradox involves an argument that purports to show the impossibility of… something. Sometimes the argument is explained as trying to show a surprise quiz is impossible. I don’t think that works for reasons I won’t belabor.

The argument could also be taken as trying to show knowledge of a surprise quiz on day 1 is impossible. So suppose for reductio that the student knows on day 1 that there will be a surprise quiz. Suppose that at the end of day 4 there has been no quiz. We assume if there’s been no quiz by a certain point, then the student knows that. So at the end of day 4, the student knows there’s been no quiz. And therefore, it would seem, he knows there’ll be a quiz on day 5. But a quiz that is known to happen on a certain day is not a surprise. Therefore the quiz can’t happen Friday.

Then you go through the same process for the other days, ultimately proving the quiz can’t happen any day. And therefore the student doesn’t know there will be a quiz.

I assume that the argument is supposed to deduce this or that. I.e. it’s not just that certain assumptions make certain consequences likely but that they follow logically.

The argument fails at the step that says the student knows on day 4 there will be quiz on day 5. It’s a rudimentary mistake. Just b/c he knows on day 1 that there’ll be a quiz it doesn’t follow that he still knows on day 4 that there will be a quiz. It’s not in general true that knowing something one day will guarantee that you continue knowing it later. There’s nothing in the argument to make one think the student’s knowledge does survive changing circumstances here.

The exercise is meant to deduce something. No principle has been presented to suppose the student’s knowledge must survive in this case. So the appropriate response is that the argument does not establish what it set out to establish since there is no reason to credit its critical inference.

But…

At the end of day 4 the student thinks back and remembers believing on day 1 that there would be a surprise quiz. We might wonder whether the student knows on day 4 that he knew on day 1 that there would be a surprise quiz.

Suppose knowledge is true belief in internal and external circumstances conducive to knowledge. The student is special. He will know something in this context iff the proposition is available to be known. The student’s internal and external circumstances on day 4 are conducive to knowing whatever he knew on day 1. So it seems the student should know on day 4 that he knew on day 1 that there would be a surprise quiz.

Knowledge that P at t entails that P is true at t. And being special, the student knows the entailments of the things he knows. So he knows that his day one knowledge entails that it was true on day 1 that there would be a surprise quiz.

It would seem that if the student knows p (that he knows on day 1 there will be a surprise quiz), knows p entails q (that his knowledge on day 1 that there will be a surprise quiz entails that it’s true on day one that there will be a surprise quiz), then he knows q (that it’s true on day one that there will be a surprise quiz).

Now we have that on day four the student knows it was true on day one that there will be a surprise quiz this week. That seems to get us back to the student having the impossible knowledge that there will be a surprise quiz on day five.

That’s where I’ve been stuck for a while. Maybe we can say there’s no guarantee that day 1 knowledge will lead to day 4 knowledge of day one knowledge.

What topics is he interested in?

Seems like your response to the 10 coins example is to reject the hypo. Surely it is possible for Smith to have the belief that whoever will get job has 10 coins in his pocket. As it is also possible for him to believe Jones will be the job winner with 10 coins. The former belief - about whoever - is justified, true, but not known. And thus a counter example to JTB.

I buy it 👍

I’m sure you’re right that many conspiracy theories are true. I just find your argument specious. Aren’t you saying:

Some Fs are Gs. These 1000 things are Fs. Therefore, some of those 1000 things are G.

I would say this is not something self-described philosophers would think of as coming in their wheelhouse. It seems like the intersection of psychology/sociology something like that.

It’s an interesting subject no doubt. Just not particularly philosophy.

Why isn’t this like: statistically it’s just not possible for all 1000 men in a sample to be less than 100 feet tall? What are the odds? At least one of them surely is 100 feet tall or more.

As someone who has a permanent severe mental illness - bipolar disorder - I have a strong view on your first question. 100% of our focus wrt laws on people such as myself should be on improving our lives. (My life is pretty sweet as it happens.) I've met many many people like myself and definitely never met a single one whose life could not be improved through medication, therapy - and you know, love.

Why is being located at every space and every time better than not being...? Is being six feet tall better than being five tall? Is being 50 years old better than being 40 years old? Is this principle only apply to occupying all of space and time vs. occupying less-or-no space and time at all?

It seems like you are missing the thrust of the number 5 example. Here goes again. Possible: math professors get together to discuss (er) math. Possible: after much deliberation, math professors announce that 5 is not a number. They’ve recalculated, so to speak.

Do you agree the above are possible? So far we’re just talking people doing things of varying degrees of normalcy and weirdness.

Then enters philosophy: how should I as a person who strives to be cognitively responsible, respond? I assume I can’t just waive it out of hand. A lot of weird stuff has been discovered. Allegedly, a spatially located object could be neither in location A, nor B, nor… That’s a thing right? I mean if that weren’t already a thing and physicists announced it tomorrow, I’d say: what the what. Pass the joint, physicists.

Again: what mathematicians say don’t make it so it not so.

Thanks for the response. There’s a lot there so I’ll just respond to a few.

First a very minor thing. I don’t think I was aware of this hot dog/sandwich thing. However, it seems to the situation as far as whether a hot dog is or is not a sandwich is surely dramatically different from whether Pluto is a planet. (I think that’s better as an example than the thumb or color situations, for reasons that I’ll perhaps get to.) With Pluto I take it at a broad level of description people are looking at whatever data, trying to systematize it in accordance with whatever empirical/logical criteria. And they say Pluto is or is not a planet.

Are there people looking at data trying to systematize analogously to figure out whether hot dogs should be classified as sandwiches in our best empirical theory of edibles? I guess sandwich and planet seem to me like relevantly different kinds of concepts with respect to a potential effort to discover how they carve up reality. But I’m open to persuasion on this.

As far as green being a color: I don’t think mainstream physics says green isn’t a color. I think they claim to have discovered the (admittedly surprising) nature of green and color, which is whatever involved fact about light and reflection and whatnot.

I am reticent to acquiesce in a conclusion by a group of investigators that really seems in conflict with how I thought my concepts worked at a basic level. Thus the 5 is not a number example. I imagine you’d be reticent to acquiesce in that alleged revelation?

Context: It’s interesting you mention that because I’ve been thinking along those lines for thumb, Pluto, etc. We take our concepts (I know you don’t like that term!) to connect up with reality as a team. So the scientists do whatever ferreting about planets and discover the whole affiliated team fits better if Pluto is not a planet. I assume my concept is theirs and therefore there is this chain reaction whereby I don’t think of Pluto as a planet.

I really should study in detail what these people are drawing on in the various examples (Pluto, time, thumb, monkey). I guess one thing I suspect is that they don’t care much about being faithful to a common concept of planet or finger or whatever.

I agree on the importance of context I think generally. But I think pretty much the same questions remain about the relationship b/been my planet classifications and the astronomers.

I apologize if i said something to suggest I believe mathematicians made it the case that 5 is a number through some actions of theirs. I definitely do not believe that. But the hypo remains re the mathematician convention etc. That seems intriguing to me. But maybe it doesn't seem like an intriguing hypo to you. Or not possible. Or whatever.

So you’re familiar with some of the further intricacies of the Pluto development. That’s cool. Is it true that Pluto is considered a dwarf planet? If so, that makes the idea that Pluto is not a planet puzzling in a different way. Generally speaking, blank planets are planets, just as far as how English works. I gather the phrase or its elements work differently here.

I don’t see the relevance of multiple languages since the phenomenon (Pluto, thumb, red) is intralinguistic.

You say it’s not an issue of authorities but you elaborate by emphasizing how what happened with Pluto was not a decision. That puzzles me.

I think you’re right that it’s not a matter of authority. I think the international astronomical union could look at the data, make some calculations, and make a false inference. I believe that’s how our concept of planet works. (Unlike say the supreme court’s interpretations of some legal issue, which arguably are dispositive.)

The thing that is distressing to me is how the theoretical adjustments can impact paradigmatic cases.

Don’t know what you mean by a tipping point of human biology. The number example had occurred to me. I gather you think you know that 5 is a number. Isn’t it possible that mathematicians concluded an annual convention just yesterday where they reassessed - as they do every year - how math should be understood? One of their conclusions was that 5 is not a number. It never has been. I assume the proper attitude isn’t to waive that hypothetical assertion out of hand, right? You should go look at the data, inferences etc to see if the whole new theory works. Which I gather is what the astronomers did for Pluto and what I could do for the thumb.

My 9-year-old daughter told me the other day that the thumb isn’t a finger. I was floored, naturally. Apparently the situation Is more complicated as far the thumb/finger but there is the anti-finger school of thought.

But I care about the general moral. Which is- or could be- that I can be mistaken about a seemingly really basic aspect of a concept in that way.

This is well-trod territory post-kripke, but it is only hitting home for me now.

Of course many people found it disconcerting when the authorities concluded that Pluto wasn’t a planet. In retrospect the remarkable thing about that development is that it …

I researched the Pluto thing for 5 seconds and saw that the international astronomical union decided that Pluto is a dwarf planet. That’s still a planet, right? Short people are still people. So I don’t know what is the deal with Pluto.

Anyway, I think the fact about the thumb that is disconcerting is epistemological. I was brought up to think of philosophy as conceptual analysis. One could discern the nature of knowledge by learning which things one would apply the concept to (and which not). But my classification of things apparently can be dramatically wrong as a result of how other people are using that concept. (Or I guess what is the same concept.)

Some questions. Could the authorities conclude that green isn’t a color? Suppose physicists announced that. I think I want to say they could be wrong. The fact that the authorities announce a classification doesn’t make it automatically right. But could it be right?

I suppose the issue is internalize/externalism about. I don’t feel like I have very good evidence to rule out that there are authoritative communities saying that temporal passage is whatever or properties are such and so. But maybe I don’t need evidence. Maybe as long as I believe whatever about my concepts on the basis of reliable mechanisms and there in fact are not such groups out there then I know.

I don’t get it…