a premise that comes from where? Why would one of these blue eyed people think of that particular premise?

what is 2? What do you call that? It's not part of the setup. It's not a known fact about the scenario. It's also not a necessary consequence of the scenario setup.

It's not even an assumption. This blue eyed person doesn't just immediately start assuming everyone has committed to the rule.

What is it?

okay so if that's not valid, then when you start out unsure if you're on an island with m blue eyed people or m-1 blue eyed people, you can't rely on it being true that "if there were m-1 blue eyed people, they would have left in m-1 days - therefore there are more than m-1 people with blue eyes, therefore I can leave on night m"

Because that's what this is about at root. There are only 2 possibilities from the perspective of a blue eyed person: either there are m-1 blue eyed people, or m. He's trying to deduce which world has in.

If he's waiting to see if m-1 people maybe don't leave in m-1 days, but it turns out to be FALSE that m-1 people would leave in m-1 days, then waiting for that doesn't tell him what world he's in. He could be in a world where m-1 people have blue eyes, or m people have blue eyes.

These guys don't want to get tortured for eternity. They can't rely on iffy reasoning. They have to be SURE. No guessing allowed. Only deductions.

So if it's at all possible that m-1 people WOULDN'T leave in m-1 days, then we absolutely cannot then say, "oh well I didn't see m-1 people leave in m-1 days, so therefore there must be m blue eyed little"

So if m is 100, each blue eyed person sees 99 blue eyed people and they, as perfect logicians (not perfect planners, not perfect committers to rules), have to ask themselves, can I really be sure 99 people would leave in 99 days? If they're anything less than deductively sure, they can't leave in 100 days.

and I'm trying to talk to you about that. You have this here:

if the n
people I see with X
eyes don't leave on day n

so that means, surely, that it's completely agreeable when I point out that your logic relies on this also being true:

If there are only 99, they'll leave on day 99.

if I don't agree with your conclusion we can't continue. Yeah okay buddy. I don't know why you want to talk to anybody lol. This is a philosophy forum. We can disagree with you, don't be weird about it.

sure it follows. This is a deduction puzzle. You see 99 people with blue eyes, you have two possibilities: either you're on an island with 99 blue eyed people and you don't have blue eyes, or 100 and you do.

Surely your logic involves the following statements at some level, implicitly or explicitly:

If there are only 99, they'll leave on day 99.

If there are 100, the 99 I see won't leave on day 99.

No?

Your insistence that if my reasoning works for 100 then it must work for 1, and so that if it doesn't work for 1 then it doesn't work for 100, is false. — Michael

You're skipping steps again. Usually you skip up - you go from some low number, get tired of thinking about that, and skip all the way up to 100. Now you're doing the opposite - you're going from 100 straight down to 1.

Don't. Skip.

Be patient, take it one step at a time

I didn't say if it works for 100, it must work for 1. I said if it works for 100, it works for 99. If it doesn't work for 99, it can't work for 100.

they can't count themselves. They can count everyone else

can you describe what the problem is?

do you still think that, or you just used to think it?

It represents a guiding force, or even higher self, which directs one's life. — Jack Cummins

Holy shit, can you fire your daimon and get a new one? If that's their job, my daimon needs retraining.

This is actually kinda usual for this particular puzzle. I brought this up on another forum 12 years ago and the same thing happened - someone with more or less the same position as Michael went on for pages and pages about why everyone else was wrong and he was right. He did come around in the end.

What do you think it explains about the forums?

I'd be willing to explore his angle too but he doesn't bite on anything!

Like I tried to meet him where he is, at 100, and it took him a long time to come around to the idea that his logic for leaving on day 100 relies on it being true that if there were only 99, they'd leave on day 99. But eventually, I got him to see that, I think.

And so then I said, so surely in turn it's true that "if there were only 99, they'd leave on day 99" relies on it also being true that "if there were only 98, they'd leave on day 98". For some reason that just doesn't compute for him. Applying the same logic he's applying to n100, to n99... that's where I lose him.

He's so ultra focused in on 100 that he refuses to look at any of the surrounding logic.

Seems like he just wants to conclude that his logic works, not look at it, not have it be questioned, end of story. Which is fine but like... keep it to yourself then lol. That's not much fun for the rest of us.

Okay, then how would a body behave in the absence of this freely choosing soul? — ToothyMaw

That's up to people who think we have souls to argue. But it stands to reason that they'd have to say bodies would do something different without souls - otherwise, souls wouldn't make a difference.

Free will is a challenging topic

If we were to choose one course of action over another according to the will of said soul, would it truly be causing matter to behave in a way that it otherwise would not have? — ToothyMaw

If it weren't, then it seems you could remove the soul and expect a person's body to behave the same way.

Which seems weird, especially because our bodies write things about having souls. Why would a body without a soul write about having a soul?

There's one way scientifically to discover souls exist, and that is to discover some significant physical behaviour inside of a brain that cannot be explained by matter behaving like normal matter. If all matter in the universe behaves like normal matter, then human behaviour by extension would have to be a consequence of matter behaving like matter.

The hypothesis that there's a soul, however, is the hypothesis (it seems to me) that some non matter "mind/soul" thing is reaching into the universe and changing something about the behaviour of matter, making it do one thing when it otherwise would have done another thing.

It doesn't seem in principle impossible to detect such a thing, though it might be so difficult that it's practically impossible anyway. Especially if the interface between the soul and the physical world is only to be found in the most microscopic physical events in the brain, like the kinds of events that determine if a neuron would fire or not.

(Personally, I don't find there to be a need for souls or minds to be nonphysical)

I swear to god it will be easy to convince him if you just convince him to start with small numbers. He's allowing himself to get confused by the number 100 and 99. There's at lot less room to get confused at 2, 3, 4. He's already admitted it's impossible at 2. He's half way admitted it's impossible at 3.

Nobody will ever come any closer to agreement as long as we focus on numbers we can't even completely imagine.

I think maybe it makes this one not correct. Maybe you have to say more, like the plane crashed because the bomb went off and it broke the left engine - because without specifying the left engine bit, saying the bomb caused the plane to crash is a bit like saying this person's poverty caused their crime.

macroscopic causality is always a bit fuzzy around the edges. Someone concludes the plane crashed because someone exploded a bomb on the plane. Does that mean all times a bomb explodes on a plane, it will result in a crash? Or just sometimes? If it's just sometimes, it seems like it's not the whole story of causality. A lot of instances of macroscopic causality are like that - it feels like you've sufficiently explained the chain of cause and effect but there's stuff left out

we agreed that it can't work for 2 people. 2 people don't leave on the 2nd day.

You seemed to understand why that means it can't work for 3 people, so if there are only 3 eyed blue people, we also know they won't leave on the 3rd day.

Do you see why that means it can't work for 4 blue eyed people, why they can't leave on the 4th day?

If you are patient and take this seriously, I'm pretty sure you'll find what I have to say compelling. But we gotta start small.

well then that logic should work when there are just 3 blue eyed people. But it doesn't.

I really want you to consider the lowest possible number this can work at, so we can actually analyse it without being confounded by big numbers.

Why would they commit to 3?

if there were only 99, then no they wouldn't think it's not possible for blues to leave on day 98. That's what we're reasoning about. We're reasoning about "if there were only 99". If there were only 99, they WOULD think it's possible for the 98 they see to leave on day 98, if your logic holds. They would have to

No, that's false. Although both statements are true, neither depends on the other. — Michael

Why would 99 leave on day 99 if they didn't reason that only 98 would leave on day 98?

You're saying 100 would be able to leave on day 100 because they're reasoning that if there were only 99 they would leave on day 99. Why do you think it's different for 99? Surely the proof for 99 leaving on day 99 is the same - surely it relies on it being true that only 98 would leave on day 98, just as much as 100 relies on it being true that only 99 would leave on day 99.

Philosophically physicalism (as a rational position) does not hold all the answers and it is more than reasonable, in many ways, to take other positions seriously — I like sushi

I think they should be taken seriously too! I'm not implying otherwise.

I do see a lot of people not talking physicalism seriously, which I think is odd and getting even more odd every day now that we live in a world where computer simulacrum of neurons are capable of speaking to us.

I'm not saying anybody is going to leave on day 98. I'm saying the statement, "if there were only 99, they would leave on day 99" can only be true if it's also true that "if there were only 98, they would leave on day 98"

Otherwise, how could it be true that "if there were only 99 they would leave on day 99"?

right, and in order for that to be true, that only 99 would leave on day 99, then it must also be true that only 98 would leave on day 98, right?

okay let me rephrase, I thought you would understand my more casual phrasing:

Your logic relies on it being true that if there were only 99, they would leave on day 99. That's what I meant by "If your reasoning works, then it must be true that 99 leave on the 99th day. Right?" Forgive my sloppy wording.

Do you agree with the new wording?

No.

My reasoning is: if the 99 blue leave on the 99th day then I am not blue, else I am blue — Michael

I'm really not trying to be sense here but, doesn't that make the answer to the question "yes"? Yes, if there's only 99, they leave on the 99th day.

well one side has something to do - the physical side has literally every bit of research they've been doing and are continuing to do. They obviously don't have all the answers, but they're also obviously trying and progressing.

The other side hasn't made a single inch of progress in thousands of years.

I know that might sound unfairly dismissive, but I also believe there's at the very least a big dose of truth in it.

Imagine rather, that there are 3 blues, 5 browns, 1 green, and you. You know thus that everyone can see at least 2 blues if they are blue, and at least 4 browns if they are brown and so on. — unenlightened

I was imagining myself as one of the blues though, putting myself in the place of BL1. That's what I was going for

If we assume that the participants are numbered, each participant asks himself "is there some X and Y such that #X does not know that #Y knows that #101 sees blue?".

And just to be clear, we can apply this to 3 blues.

Imagine 3 blues and 5 browns and 1 green.

BL1(#X) sees 2 blues, and looks at one of them (#Y) and knows that he sees at least 1 blue, and because #Y sees at least one blue, #X can reason that #Y also knows that guru sees at least one blue.

So if this is truly the basis of the reasoning, it has to work at 3 blues.

It might not be the explicit premise you're trying to focus on, is what I'm saying, but it's still a direct consequence of the reasoning you're trying to apply. If your reasoning works, then it must be true that 99 leave on the 99th day. Right?

That's not my premise. — Michael

So if the 99 you see leave on the 99th day, on the 100th day you'll conclude you have blue eyes anyway?

Then go through all the numbers and for each number imagine the participants asking themselves "is there some X and Y such that #X does not know that #Y knows that #1 sees blue/brown/green?" — Michael

X knows that everyone knows that guru sees blue at 3 blue. But we've already established that 3 can't leave on the third day.

You're trying to address the problem, but this is a deduction puzzle, and your deduction has a false premise. The premise that's false is 99 blue eyed people would leave on the 99th day.

But for me to show you that's false, I would have to show you that it's false that 98 people would leave on the 98th day.

And to prove that's false, I would have to prove to you that it's false that 97 people would leave on the 97th day.

And so on.

That's a lot.

But here's the deal- you keep counting down, 99 98 97... eventually you get to 3. And we know 3 don't leave on the third day.

It's easier to talk about small numbers than big numbers.

Okay, well I think the answer is that there isn't a difference — Michael

Just to recap, We've already agreed that it does make a difference for the case of one blue eyed person, and two, and three. There must be some number where it starts making a difference. I'm very interested in that number. You want me to accept that it starts making a difference some time before 100 - if I'm going to accept that, I'm gonna need you to show me when.

For every number of blue eyed people x, your reasoning seems to rely on the premise that if there were x-1 blue eyed people, they leave in x-1 days. You're obscuring your logic by jumping to 100 blue eyed people. I'm trying to explore with you the numbers that aren't obscured.

okay so I dare you to not leap to thinking about 100, and think about smaller numbers. We've talked about 2, we've talked about 3, I think we agreed 2 can't leave on the second day, I think we agree 3 can't leave on third. Can 4 leave on the 4th?

But what's the relevant difference between seeing a piece of paper with the words "there is at least one blue" written on it and seeing 99 blue? How and why is it that the former can "cut through this recursive epistemic conundrum" but the latter can't? — Michael

That's what makes this puzzle so interesting. Truly, that's one of the biggest points, and why people find it fascinating. It's weird. It's hard to explain, it's unintuitive, but if you work through the logic from the ground up, it's nevertheless true. For some reason, it makes a difference.

This is the logic being discussed, right?

1. As of right now everyone has come to know, through some means or another, that everyone knows that #101 sees blue
2. If (1) is true and if I do not see blue then I am blue and will leave this evening
3. If (1) is true and if I see 1 blue then if he does not leave this evening then I am blue and will leave tomorrow evening
4. If (1) is true and if I see 2 blue then ...
...

And it bears repeating (if any reader missed the previous comment), that even though as a practical matter (1) is true in counterfactual scenarios (2) and (3) only if someone says "I see blue" isn't that someone must say "I see blue" in every counterfactual and actual scenario for (1) to be true and for this reasoning to be usable.

But we already have a simple, straight-forward case that this logic doesn't work. We know, because he's already acknolwedged, that 2-blue-eyed doesn't work. 2 blue-eyed people cannot leave on the second day.

If it's true that 2 blue-eyed people cannot leave on the second day, then it must also be true that 3 blue-eyed people cannot deduce that there's more than 2 blue-eyed people just because they don't leave on the second day. So 3 blue-eyed people cannot leave on the third day.

But premise 1, "everyone has come to know, through some means or another, that everyone knows that #101 sees blue", is true in the case of 3 -- and yet it still doesn't work.

So we have a tangible, specific case where Michael should be able to apply this logic, and yet can't.

It genuinely feels like these simple cases, for low numbers of blue-eyed people, are being ignored because it's easier to hide the reasoning behind the obscurity and confusion of very large numbers. The beauty of unenlightend's logic is that it clearly unambiguously works for small numbers, and so we can work our way up to large numbers. In contrast, Michael's logic, we know for sure doesn't work for small numbers, so instead of working his way up to large numbers, he just kinda ignores the problems at small numbers and hopes nobody notices the gaps in logic once there's 100 people to talk about. It's easier to hide the cracks with so many blue-eyed people to think about.

If Michael wasn't so worried about getting tortured for eternity, I'd be encouraging him to find the lowest number of blue-eyed people that it works for. Michael it's only a fictional torturing for eternity.

I do not think causation is one, though — AmadeusD

Causation itself isn't even in the category of things we're talking about. It's the meta-category of those categories of things. Minds interacting with bodies is a type of causation. Heat causing x or y is in the category of causation.