Hello again.

Knowing nothing else, indeed the probability of a true perception is 1/2, and a false perception is 1/2, and thus the probability of X, Y and Z all having a true perception is 1/8, and all having a false perception is also 1/8.

But we know something else: All three perceive the same thing P.
This new knowledge changes the probability. To simplify, let's suppose they can only perceive 10 different things ever. The probability of all three perceiving the same false perception P is now (1/10)*(1/10)*(1/10)=1/1000. Since the only alternative is a true perception, that probability is 1-(1/1000)=999/1000.

Knowing nothing else, indeed the probability of a true perception is 1/2, and a false perception is 1/2, and thus the probability of X, Y and Z all having a true perception is 1/8, and all having a false perception is also 1/8.

But we know something else: All three perceive the same thing P.
This new knowledge changes the probability. To simplify, let's suppose they can only perceive 10 different things ever. The probability of all three perceiving the same false perception P is now (1/10)*(1/10)*(1/10)=1/100. Since the only alternative is a true perception, that probability is 1-(1/100)=99/100. — Samuel Lacrampe

Hi. Sorry for the distraction. I'm sure you had better things to do.

You might want to take a closer look at what I underlined.

The probabilities of outcomes change based on your knowledge of the system. As the knowledge in the first paragraph above is different than the one in the second paragraph, the probabilities are different.

The probabilities of outcomes change based on your knowledge of the system. As the knowledge in the first paragraph above is different than the one in the second paragraph, the probabilities are different. — Samuel Lacrampe

Indeed they do. Firstly, what exactly do you mean probability of a false perception is 1/10? As I mentioned before, any number other than 1/2 needs to be justified for it's assuming the very thing that has to be proven viz. it's more likely that a perception is true (your value for the probability of a true perception is 9/10).

Secondly, I'm not making any claims about the chances of perceptions being real/hallucinations apart from assigning it the reasonable value of 50% or 1/2 and assessing how increasing the number of perceivers affects this probability.

My interest lies in whether increasing the number of perceivers has any effect on the likelihood of a perception being real or hallucinatory.

Have a look below:

X: chance of perception being true/hallucinatory = 50% = 1/2
Y: chance of perception being true/hallucinatory = 50% = 1/2
Z: chance of perception being true/hallucinatory = 50% = 1/2

Chance that all three are perceiving something true = (1/2)*(1/2)*(1/2) = 1/8 = chance of all three hallucinating.

Adding more perceivers will not make a difference as the probability of a "collective hallucination" = probability of true perception.

@Outlander @prothero

I've made a boo-boo. Samuel Lacrampe is correct - the more people reporting a perception, the more likely is the perception to be real/true. The probability that everyone is hallucinating (collective hallucination) decreases with the number of perceivers reporting a perception.

Still in a fog I must say :chin:

Right on.
Also I have edited my previous post: (1/10)*(1/10)*(1/10)=1/1000, not 1/100.

I'm not quite sure about it yet.

The probability that X, Y or Z is hallucinating/not hallucinating = 1/2 = 50%. By "not hallucinating" I mean the perception is real.

Notation: P(t) = probability that t is true, Hx = X is haullucinating, Hy = Y is hallucinating, Z = Z is hallucinating

1. P(Hx) = 1/2
2. P(Hx) & P(Hy) = (1/2)*(1/2) = 1/4. P(not that both are hallucinating) = 1 - (1/4) = 3/4
3. P(Hx) & P(Hy) & P(Hz) = (1/2)*(1/2)*(1/2) = 1/8. P(not all three are hallucinating) = 1 - (1/8) = 7/8

As you can see, as the number of people reporting a perception increases, the probability that all of them are hallucinating at the same time decreases.

However note the following:
4. P(~Hx) = 1/2
5. P(~Hx) & P(~Hy) = (1/2)*(1/2) = 1/4. P(not that both are perceiving something real) = 1 - (1/4) = 3/4
6. P(~Hx) & P(~Hy) & P(~Hz) = (1/2)*(1/2)*(1/2) = 1/8. P(not that all three are perceiving something real) = 1 - (1/8) = 7/8

The probability of a collective hallucination decreases with the number of people reporting a perception but that doesn't seem to translate into an increased probability that everyone is perceiving something real.

Please get back to me with your insights into the matter.

2. One male and one female and about 18 years of waiting.

I either have an egg in my house, or I have some chocolate fondant in my house.
The principle of indifference gives both 50% odds.
I actually have neither.
So I have a 0% chance of having either.

You can't just throw probabilities out like that, you end up with absolute nonsense. If you want to apply the principle of indifference, it should make sense; not be applied over an arbitrary outcome set, you have to be super careful with it.

If you contradict yourself then everything becomes nonsense.

Your assessment is correct under the condition that we know nothing about the perceptions. It is equivalent at this point to guessing the results of tossing 3 coins.

But once we add the information that all three subjects always perceive the same thing, then the probability calculation changes completely. It is a lot more like rolling 3 dice, and knowing that the results are always 6-6-6, we are then inclined to believe that the dice are loaded.

The perception, what is perceived, isn't the issue. People may agree on that. What we don't know is if that perception is real or not.

that's a pretty common - meaning asserted by people from a wide range of epistemologies and intentions - assertion, that what seems true to you actually isn't.

Yeah. Had a version of it over in another forum in a thread about Mike Flynn.

The guys comment essentially was, "He did not lie. He just didn't tell the truth because he wanted to protect his son."

To be technical, all perceptions are real; it is a matter of finding if they are true or false.

To be technical, all perceptions are real; it is a matter of finding if they are true or false. — Samuel Lacrampe

I guess it's a question of how one uses the word "real". I meant to distinguish between hallucinations and its opposite, reality.

1. An individual/one person's report doesn't count as a strong enough foundation to believe that what this person perceives is real. How is it then that a group of people's report of a perception is taken as adequate grounds for believing a given perception is real? After all the group consists of individuals. It's like saying that a group of blind individuals can see even though each and everyone in the group is blind. — TheMadFool

Blind people cannot see. People's perceptions are fallible. Blind people reporting things that must be seen to be noted are right only coincidentally. The cannot possibly have seen anything. Fallible people might often be right.

And the truth is we often believe what 1 person says. If you tell me you had a bad night's sleep and there is no reason for me to suspect you might have a motive for lying, I am safe, in general, taking such things as true. If you say you exploded into a mass of pulp and blood over breakfast this moring, I will want some more evidence than your account.

Depending on what is asserted and who is asserting it a single's person's account may be taken as true, possibly true, and every other gradation down to false.

Once we note that unlike blind people, fallible people can be often right, but this does not mean what we consider less likely need be accepted without more evidence, we have a very complicated situation.

The advantage of more observers is that some possible reasons for being confused, deluded, psychotic, start to reduce. This becomes even more likely (the reduction) fi the people do not know each other or have a common reason to make up/hallucinate/lie/misinterpret what they claim they have seen. Science tries to reduce all these factors with strict protocols.

You take one blind person and ask them what is in an image projected on a wall, then ask more blind people what they see, this does nothing to reduce their full on inablity to see. The exact same experiment, with a photo of a duck projected on a wall, reduces the factor of one person's fallibility in identifying the image. It's not a good analogy and it is not binary.

How is it that while one individual's testimony has zero credibility, a group of people, composed of individuals as it were, enjoy a special status as far as believability is concerned? That's all I'm concerned about.
https://m.youtube.com/watch?reload=9&v=Zk8iRVpIjd8


https://m.youtube.com/watch?reload=9&v=Zk8iRVpIjd8

How is it that while one individual's testimony has zero credibility, a group of people, composed of individuals as it were, enjoy a special status as far as believability is concerned? That's all I'm concerned about. — TheMadFool

HOnestly, it seems like you didn't read what I wrote. I directly challenged the ideas that an individual's testimony has zero credibility and that the whole thing is binary. I don't think anyone follows these ideas in practice anywhere, regardless of their epistemology. Even the most rigorous scientist takes her husband's testimony, for example, on all sorts of things. Some things less, and if he said some things very little. But heck, I went into all of this in my previous post.

Can you give me a link to a short video that could explain your misgivings regarding my claims?

Yeah that's indeed what I thought you meant. I'm just being nit-picky.
For general info though, "truth" is "conformance to reality", where as "real" means "exists outside the mind (contrasted with imaginary)". As such, all perceptions, insofar that we experience them, are real. And if the info they provide conforms to reality, then the perceptions are true, and false otherwise.

Yeah that's indeed what I thought you meant. I'm just being nit-picky.
For general info though, "truth" is "conformance to reality", where as "real" means "exists outside the mind (contrasted with imaginary)". As such, all perceptions, insofar that we experience them, are real. And if the info they provide conforms to reality, then the perceptions are true, and false otherwise. — Samuel Lacrampe

Well, we are discussing the difference between hallucinations and reality. For a perception to be "real", the object of perception must be outside the mind and not something the mind creates.

A video? I don't know exactly how to even search for one. Every human I have ever met accepts the testimony of individuals for all sorts of assertions. I gave examples. The court system validates as evidence ALL THE TIME the testimony of individual witnesses. Yes, often this needs to be bolstered by, for example, physical evidence. but it, as you assert, it was givne zero value NO lawyer would waste everyone's time calling witnesses. We all weigh a number of factors into decding whether to accept one person's claim: their history of cliams we know of, their expertise, their potential motives, how likely they were in the right place and so on, the exceptionalness of the claim, what we already believe in general and more. But to say we give zero value to one person's seeing/claim/assertion does not fit everyday reality in the least. I find it hard to believe anyone made a video showing this. We all, for example, go to experts ALL THE TIME, and often only in extreme situations (cancer diagnoses, for example) do we go for a second opinion. And when we do this does not mean, generally, that we consider the first opinion to have no value. Not considering it necessarily 100% correct does not mean it has no value.

Now if we are talking about scientific contexts only, again, individual observations are included in all research, but to gain acceptance as a theory, for example, rather than a hypothesis, we require more individual observations by individuals, and rigorous control of potential other factors. This is to reduce the potential problems an individual observer might have (misinterpretation, bias, mistakes). None of this reduces the single observer to having no value. That single obersvation simply does not have enough value (note!!!!! not binary, we are talking about degree of value). So when you add up things with not enough value in and of themselves,you are adding up some degree of value to a level considered rigorous enough to be consider ENOUGH value. Degrees of value.

If for some reason this is still unclear or you still want a video, perhaps someone else is a better interlocutor for you than I am.

But to say we give zero value to one person's seeing/claim/assertion does not fit everyday reality in the least. I find it hard to believe anyone made a video showing this. We all, for example, go to experts ALL THE TIME, and often only in extreme situations (cancer diagnoses, for example) do we go for a second opinion — Coben

Now if we are talking about scientific contexts only, again, individual observations are included in all research, but to gain acceptance as a theory, for example, rather than a hypothesis, we require more individual observations by individuals, and rigorous control of potential other factors. This is to reduce the potential problems an individual observer might have (misinterpretation, bias, mistakes). — Coben

The two excerpts above from your post don't square with each other. On one hand you claim individual perceptual testimonies are evidentially sound and on the other hand they're not and require extra support by way of additional perceptual testimonies of other individuals.

As far as I'm concerned if one person's perception can't be trusted, I don't see how a group of persons justifies a change in our level of trust; after all, the group is composed of individuals, no?

That single obersvation simply does not have enough value (note!!!!! not binary, we are talking about degree of value). So when you add up things with not enough value in and of themselves,you are adding up some degree of value to a level considered rigorous enough to be consider ENOUGH value. Degrees of value. — Coben

Why are you insistent about this binary-nonbinary issue so much. As I see it, either

1. a perception is real

OR

2. a perception is not real - a hallucination