Well we never specified the barber's gender, so they could be a girl, so she doesn't have to shave, and because she is a girl that does not shave herself instead of a man that does shave himself she doesn't have to shave herself. So the barbers a girl.
It's not the barber that doesn't exist. It's the relation 'shaves' that doesn't exist.
Suppose there is a man living in the village who is the barber. Suppose further that there exists a binary relation 'shaves' defined on the set of all men in that village such that the barber 'shaves' those and only those men in the village who do not shave themselves. You can resolve the paradox by showing that no such relation can exist. See my video, "The Barber Paradox, A Mathematical Analysis."
I remember we learned the barber paradox in philosophy class. It was simply called Russell's paradox, or paradox of sets. Negative Self-inclusive sets don't exist; a good argument against the existence of God. Russell is great; Russell's teapot seems widely known on YouTube, but many don't fully reach the endgame of its logic.
Why is it a contradiction? There's no such person who shaves all those who don't shave themselves, and shaves no one else.
I've come up with a similar contraction. I am thinking of a number that is equal to 3, and is not equal to 3. Well, if the number I'm thinking of is equal to 3, then it can't not be equal to 3. If it is not equal to 3, then it can't be equal to 3. Contraction? No. The problem is there is no such number.
The problem is in my claim, that I'm thinking of such a number.
A contradiction is expressed as P and not P at the same time, where P is a proposition. The proposition here is that the barber shaves only all those men of the village that do not shave themselves. No such barber can exist. If he shaves himself then he cannot be the barber that only shaves all those men of the village that do not shave themselves and if he does not shave himself then he cannot be the barber of the village that only shaves those men who do not shave themselves.
This is a nice variant to the paradox regularly used in artificial intelligence research (obviously Russell predated AI ;) ):
The paradox used in AI is simply: "Nothing I say is true, not even this."
This conundrum cannot be resolved by Boolean logic, but requires a logic that can handle concepts of contradiction and special handling of obviously non-factual information.
That is the contradiction, we start out saying there is this barber, and then refer to the barber by something that cannot exist (the barber that only shaves all those men of the village that do not shave themselves). So we are saying there IS a barber who IS something that does not exist. And of course there is no such thing.
Ok Greg, lets try this one on for size, i kinda thought about it while i was asleep...
Lets assume that this man is a barber during a time that time travel has been invented, so this man travels forward OR backwards in time to shave his other self that does not shave it self it is still the same person but 2 different selves (assuming there is alternate dimensions of reality and many parallel universe this would not be himself but it would be another of the same person) !!! lol
There is a woman who lives in a village and who is a nail technician. She only does the nails of all the women in the village that do not do their own nails. Does she do her own nails?
If yes, then she cannot be the nail techinician that only does the nails of the women of the village that do not do their own nails.
If no, then she she cannot be the nail technician that only does the nails of the women of the village that do not do their own nails.
Well, impossible to be a man from a village who only shaves those men of the village who do not shave themselves, yes.
It is P and not P at the same time if it was the case that the barber both shaved himself and not shave himself. A logical contradiction cannot exist, everything else is possible. It is not possible that this barber exists.
Hopefully applicable to a god that doesn't change ever (Malachi 3:6) and then does change often. (Exodus 32:14) (1 Samuel 15:35) Proof of nonexistence
There is no belief required to say this barber does not exist, excepting the axioms of logic itself. For what we can call true in any form, such as 1+1=2, it is raining out or it is not raining out (tautologous truth), or the sun is larger than the earth (empirical truth), we can show the gods of the bible and koran nonexistent. If existent is to mean anything at all, then those do not apply. That is why this video exists, to show how we prove something does not exist, no belief required.
Its too bad all gods cannot be shown to be P and not P at the same time the way christian and muslim gods can be. Then atheism would not be a belief at all.
Yet, to deny gods of deism, the heaven of buddhism (nirvana), Santa Claus, or the tooth fairy as existent requires a P and not P at the same time where I have not found one. So I'd say Santa Claus has a better chance of existing than the christian god does. This says nothing for atheism though, it is an anti-christian position itself.
Reindeer don't fly is valid, and if they did they would not be reindeer at all. So this aspect could dispell Santa and be a contradiction that the myth requires. But a myth is not a falsehood, it is not a "proven to not be", it is a myth because the only verification of it is the story itself. I could write a story right now about driving to work tommorow and seeing horses and today it is a myth, tommorow if it happens (and likely will) it is no longer a myth.
There is an assumption that the barber is an inhabitant of the village in question. In no variations that I've seen does it specifically say that the barber lives in that particular village. SO, the barber can exist if he is from a neighboring village.
Of course I've also read this statement were they don't say that the barber is a man. In that case of course the barber can exist if the barber is a female or a young boy.
Easy fix. Just state that the barber lives in the village, that the barber is a man, and that he shaves all the men of the village. That closes the loopholes.
"Easy fix. Just state that the barber lives in the village, that the barber is a man, and that he shaves all the men of the village. That closes the loopholes. "
Then he does not shave all those men who do not shave themselves, as he would shave himself.
@gklr, I understand that. I was specifically responding to sharkinfested's comment. The "flaws" that shark pointed out are not really problems because they're easily remedied with a few words here and there.
The barber can exist a couple ways. We know nothing about the barber other than that which we are told, that he shaves all those that don't shave themselves and that he ONLY shaves those that don't shave themselves.
There are people, both men and women, who are incapable of growing any body or facial hair, the barber could be one of them. Alternatively, the barber could have been tragically burned from head to toe, destroying all of his hair folicles. Let us not forget about NAIR.
A person who is incapable of growing body hair does not shave themselves; therefore, the barber in question shaves shaves that person because he shaves all those who do not shave themselves. Since that person is himself, he does not shave himself. The paradox still exists in that case, and the barber does not.
A koan does not necessarily have one answer. To suggest that there is an either/or answer highlights the limitations of rock (Western) logic. Hara (Japanese) logic has more possibilities.
Obviously the barber cannot shave himself and cannot not shave himself. The barber cannot exist. I think this video went right over your head. You missed the point entirely.
The question is, does the barber shave himself? In this form the contradiction is not very difficult to solve...I think it is clear that you can only get around it by observing that the whole question whether a class is or is not a member of itself is nonsense, i.e. that no class either is or is not a member of itself, and that it is not even true to say that, because the whole form of words is just noise without meaning. Bertrand Russell, The Philosophy of Logical Atomism
That quote shouldn't be making me the one who feels like an idiot, Greg. The Barber's Paradox didn't make as big a splash as it did because it's not difficult to solve with classical logic. It's just the starting point for discussing why logic alone is a flawed way to get to the truth, although you'd like it to be otherwise.
If that quote doesn't make you realize how idiotic your words were, then that is as funny as most of what you say. And besides, only through your misinterpetation have I said this boils down to the excluded middle rule. It is actually "P and not P, at the same time", which proves what cannot exist and the barber applies.
In quantum reality, the barber neither exists, nor does he not exist, for he is composed of 'stuff' that exhibits that same nature. And we are all barbers. ;-)
If so, then quantum reality is an utter loss. Clearly the barber cannot exist, there is no such possible barber. If a baby dies before it ever cut some hair, it was never a barber.
An object exists or not, there is no such possibie thing that is, and is not.
Perhaps zen buddhism is good for inspiring poetry, but clearly if that is the result of your inquiry into the world then I would use it as an example of why to avoid it. Utter nonsense. Quantum Quakery, not QM science. QM I respect.
You didn't read my comment correctly. I said an object neither exists nor does it not exist. No matter, this also violates your precious rules of logic, which you've admitted elsewhere cannot be proven beyond a doubt, and in spite of the fact that QM demonstrates that there are clearly conditions in which logic does not apply. You've succumbed to the same insanity that troubles theists- you've created a belief system from which you refuse to waver.
An object either exists or not. It is as impossible for this barber to exist as it is for anything to neither exist or not exist.
Quantum Quackery is not QM. You cite QQ, not QM. The laws of logic need to be assumed or there is nothing that can be said at all, including the poets.
Offer some reasoning as to how an object neither exists nor does not exist. Just reciting poetry isn't very informative.... and whatever logic you submit saying so, will clearly contradict itself.
Well, we agree here some, though not that poets need be logical. Logic and reason will not take you to the ground of reality, so you're right, there's nothing to be said, and I will surely contradict myself. But tell me, what words can be used to describe the taste of an apple, or the experience of sex, that will take the place of the experience itself? Yet clearly they are a part of reality, even if they are nothing more than someone else's dream.
Speaking of poetry, try this from Walt Whitman- "I contradict myself? Very well then- I contadict myself. I am large enough to contradict myself." Your left brain, linear mind will never see the truth in that, Greg. Dressing people down as quacks won't change the reality of what they see, and you do not. Sorry. Hostility is a sure sign of a deluded mind. Your godless world would be just as angry as this one, and far from righteous.
I pan "rightiousness" as deluded and even dangerous. Do-gooders are idiots. When I am not ragging on religion, I am ragging on those who think morality and ethics can be objective.
You are a quack because you think holding to contradictions is sensible. Whackjob material.
That's funny, Greg- you rag on those who think morality and ethics can be objective, yet you believe your opinions are absolutely and "objectively" correct. That's why you come off as self-righteous as any theist. You better start ragging on yourself! Righteousness lies beyond objectivity, in a reality you have yet to see. Of course, your ideas are quite easy to grasp, and are therefore quite popular. Enjoy your popularity, and your self-imposed bondage. A few of us whackjobs have found freedom.
That subjective opinion exists, provably and objectively, is not news. I do not say it is absolute because that would be silly after proving no absolute is possible.
You speak as poorly for me as you do Bertrand Rusell. Get your money back on those ESP lessons. lol.
This is more or less my point in commenting on your vids in the first place. Just think about that phrase, "...after proving no absolute is possible." Huh? You argue your "proofs" as though they ARE absolute. It colors your thinking and reasoning in ways you don't even realize. It doesn't take ESP to see that. When Russell was asked if he would die for his views, he responded, "Of course not- I could very well be wrong!" The implication is he probably wasn't willing to live by them, either.
That absolute truth is impossible, is itself a systemic truth, not an absolute one. It was not true before mind or language existed and could not have been. No truths existed then. No words, no statements existed then. Truth is a characteristic of a statement and only ever applies to statements. Again, you so misunderstand it is funny. If Russell or myself is wrong, show it. You don't even understand what is being said, so I won't hold my breath.
is it not, therefore the case, that the axiom which we begin with, ie, the barber shaves only the men who do not shave themselves, is not a denoting statement, like, russells example of the bald king of france. we can break this paradox down into 3 bits too, there is one man who is the barber, all the men who are the barber shave only the men who dont shave themselves, and the barber does not exist. so the 3rd premise is all that makes the barber impossible, not physical law. any of that ok? lol
There is a woman in a village who is a nail technician and who only does the nails of those women in the village who do not do their own nails. Does she do her own nails or not?
If she does, it cannot be true that she only does the nails of those women who do not do their own nails.
If she does not do her nails, then it is not true that she only does the nails of those women of the village that do not do their own nails.
The paradox you seem to be so proud of is based on a rule that he cannot shave men who shave themselves. This barber can follow this rule quite simply, he needs only to not shave himself.
The barber shaves only all those men of the village who do not shave themselves. If he does not shave himself, then he does not shave all those men of the village who do not shave themselves, which was the description.
The barber cannot shave himself and be that description, and the barber cannot not shave himself and be that description, and so the barber cannot exist as per that description, shaving only all those men of his village that do not shave themselves.
Always does not apply, since nothing occurs always. Time applies, in that you cannot provide any time when it is possible that the barber shaves himself or does not shave himself, because if either is true then it cannot be the barber who lives in this village and only shaves those men of the village who do not shave themselves.
The barber cannot exist because the barber cannot shave himself and cannot not shave himself. If he shaves himself, it is not true he shaves all those men who do not shave themselves. If the barber does not shave himself, it is not true he shaves all those men of the village who do not shave themselves.
There can be no such barber, sincet the barber cannot shave himself and cannot not shave himself.
let's call shaving others shaving and shaving oneself trimming. The barber shaves all who doesn't trim. Does the barber trim? No paradox here, though exactly the same question is put forth with a more specific vocabulary. The Barber may or may not trim (shave himself) when we recognise that shaving oneself is doing something different than shaving someone else. The premisses doesn't tell if he shave himself or not.
The barber cannot exist. That is the point of the video. This video shows how to prove what does not exist, counter to the often heard argument that "We cannot prove a negative", which is nonsense.
If the barber shaves himself, he does not shave all those men of the village who do not shave themselves. If the barber does not shave himself, he does not shave all those men of the village who do not shave themselves.
Yes I can see that is what you try to argue. You didn't address my rebuttal, which is that shaving oneself and shaving someone else isn't the same form of action, and the paradox relies on the fact that two different actions has the same word.
to do X to Y and to do X to Z is linguistically to do X sometimes though both things are completely different things (to shave Peter and to shave Roger are not to do the same thing). Sometimes it is not to do X linguistically even. (To have sex with Peter and to have sex with oneself is both not intercourse, one is masturbation). So we know that to shave someone and to shave yourself is two different kinds of actions.
but if you take out that line, then there is no contradiction and you can use that to prove that the barber cannot be not a member of the village; in other words, no village contains every barber.
I like the barbers paradox, when I first heard it I told it to my friends and we had a good time debating it :). Another paradox I like is the so called Monty Hall paradox, witch I learned about in a math class some years ago. I see you are an active atheist, posting debates to counter religion. I have no problem with that, however, I'm an atheist so I don't have to speculate about a god =) Keep it up.
Linguistic knot. It is still like the square circle though. This Barber isn't defined, because I have yet to understand what it means practically to shave oneself and not shave oneself. If that doesn't mean anything, then you haven't explained what this Barber is like.
The barber is defined as a man who lives in a village and shaves only all those men of the village who do not shave themselves. If he shaves himself he cannot shave only all those men of the village who do not shave themselves. If he does not shave himself then he cannot shave only all those men of the village that do not shave themselves. There is no 3rd option, therefore the barber cannot exist. There is no such possible barber.
I don't know what it means to shave all those men who doesn't shave themselves, as I have trouble understanding if he shaves himself or not. So you haven't explained what kind of barber he is at all. It is exactly like saying square circle, or a barber who doesn't cut anyones hair or shave anyone ever. We know not what any of these concepts mean.
The concepts are simple. There is a village with people, men live there. Of those men, one is a barber. He shaves people. He only shaves those men who do not shave themselves. Not shaving yourself means you do not take a razor and put it to your skin. Of those men who shave, they do put a razor to their skin to remove hair. There can be no such male barber, who shaves all the men of the barbers village who do not shave themselves. It can't exist.
The further necessary implications of a description is part of the concept. Therefore a non descriptive element is part of the original description. Therefore the original description describes nothing, or need to be clarified so that we understand the description.
The barber shaves a man if and only if he does not shave himself. For every man it is either true or false that he shaves himself and by the Axiom of Specificition there exists a subset of the members of the village that consists of all the men who do not shave themselves and no one else. This uniquely charactarizes the barber's actions but it does not guarantee his existence. The contradiction that follows proves his nonexistence.
Yes, it is the law of the excluded middle, introduced by Aristotle and one of the laws of logic. Every proposition is either true or false, there can be no middle. While we can believe what we want, what we believe doesn't itself show a truth.
If the barber simply lets his beard grow, then he does not only shave all those men of the village who do not shave themselves.
I see. He would not be shaving them "all" because there would be one he does not shave (himself). Excellent. I knew this conclusion would crumble, glad you found the flaw.
"All men must either shave or be shaven" is not the law of the excluded middle. All men must either shave or not shave, is. All men of the village are either members of the set of those who shave themselves or members of the set of those men who do not shave themselves. "Shave or be shaven" isn't that. The assumption is that every man shaves himself or not. My error.
I tried my best (oh goodness I did) to come up with a good reply to this. My brain is still frazzled by it. I'm looking forward to the next one... heck I am looking forward to continue this exploration.
gklr, or anyone that hasn't read it: pick up "A Brief History of the Paradox: Philosophy and the Labyriths of the Mind," by Roy Sorensen. You'll love it.
GK, I take great offense to your video. I am the barber of which you speak. I live in the village of Farada, but I am the barber to barundi. While I was in barundi a gentleman requested that I cut his wifes hair, to which I replied I only shave the heads of all the men who do not shave their own. I do shave my own head, and although this gentlemen's description of me is confusing because of the lack of context, I do not appreciate you denying my existence. It is bad for my business!
Well we never specified the barber's gender, so they could be a girl, so she doesn't have to shave, and because she is a girl that does not shave herself instead of a man that does shave himself she doesn't have to shave herself. So the barbers a girl.
humansound1 2 months ago
@humansound1,
"Well we never specified the barber's gender"
Yes we did.
gklr 2 months ago
It's not the barber that doesn't exist. It's the relation 'shaves' that doesn't exist.
Suppose there is a man living in the village who is the barber. Suppose further that there exists a binary relation 'shaves' defined on the set of all men in that village such that the barber 'shaves' those and only those men in the village who do not shave themselves. You can resolve the paradox by showing that no such relation can exist. See my video, "The Barber Paradox, A Mathematical Analysis."
dcproof1 3 months ago
You're a fan of Russell, eh? :P
I remember we learned the barber paradox in philosophy class. It was simply called Russell's paradox, or paradox of sets. Negative Self-inclusive sets don't exist; a good argument against the existence of God. Russell is great; Russell's teapot seems widely known on YouTube, but many don't fully reach the endgame of its logic.
Knr911 1 year ago
Why is it a contradiction? There's no such person who shaves all those who don't shave themselves, and shaves no one else.
I've come up with a similar contraction. I am thinking of a number that is equal to 3, and is not equal to 3. Well, if the number I'm thinking of is equal to 3, then it can't not be equal to 3. If it is not equal to 3, then it can't be equal to 3. Contraction? No. The problem is there is no such number.
The problem is in my claim, that I'm thinking of such a number.
JavaBlues 1 year ago
@JavaBlues,
A contradiction is expressed as P and not P at the same time, where P is a proposition. The proposition here is that the barber shaves only all those men of the village that do not shave themselves. No such barber can exist. If he shaves himself then he cannot be the barber that only shaves all those men of the village that do not shave themselves and if he does not shave himself then he cannot be the barber of the village that only shaves those men who do not shave themselves.
gklr 1 year ago
This is a nice variant to the paradox regularly used in artificial intelligence research (obviously Russell predated AI ;) ):
The paradox used in AI is simply: "Nothing I say is true, not even this."
This conundrum cannot be resolved by Boolean logic, but requires a logic that can handle concepts of contradiction and special handling of obviously non-factual information.
youneac 1 year ago
the barber has a massive beard.
mjjuna 1 year ago
"the barber has a massive beard."
Are you suggesting he does not shave himself?
Then it would not be the barber who only shaves all those men of the village that do not shave themselves.
This barber cannot exist since it cannot be true he shaves himself and it cannot be true that he does not shave himself.
gklr 1 year ago
Nice solution! But the way I see it it only creates a new paradox :)
The opening statement to the barber paradox is: "There IS a man"[... ] If he IS, then he must exist ;)
ethaleawa 2 years ago
@ethaleawa,
That is the contradiction, we start out saying there is this barber, and then refer to the barber by something that cannot exist (the barber that only shaves all those men of the village that do not shave themselves). So we are saying there IS a barber who IS something that does not exist. And of course there is no such thing.
gklr 1 year ago
He does not shave.
tesla2266 2 years ago
If the barber does not shave, then he does not shave all those men of the village who do not shave themselves.
The barber cannot exist.
gklr 2 years ago
The barber exists. She doesn't need to shave.
Gorteenminogue 2 years ago
Oh dear. I read the paradox on your site, and the barber's sex wasn't specified. Hence answer above was feasible.
Gorteenminogue 2 years ago
Ok, so describe the barber as simply "he who shaves all those who do not shave themselves."
redetrigan 2 years ago
But the statement says there IS a barber so it doesn't make sense to deny something that exists, right?
1yK3Y4 2 years ago
Perhaps this barbers face was burnt as a kid and he cannot grow facial hair XD
Zimph01 2 years ago
Then he does not shave all those men of the village that do not shave themselves.
gklr 2 years ago
Ok Greg, lets try this one on for size, i kinda thought about it while i was asleep...
Lets assume that this man is a barber during a time that time travel has been invented, so this man travels forward OR backwards in time to shave his other self that does not shave it self it is still the same person but 2 different selves (assuming there is alternate dimensions of reality and many parallel universe this would not be himself but it would be another of the same person) !!! lol
Zimph01 2 years ago
Comment removed
VodkaElit 2 years ago
@gklr The barber is a woman yay!
aliengrappler 1 year ago
@aliengrappler,
There is a woman who lives in a village and who is a nail technician. She only does the nails of all the women in the village that do not do their own nails. Does she do her own nails?
If yes, then she cannot be the nail techinician that only does the nails of the women of the village that do not do their own nails.
If no, then she she cannot be the nail technician that only does the nails of the women of the village that do not do their own nails.
gklr 1 year ago
@gklr a nail technician? hahah, i know i know. I understand the paradox, i was just being an idiot.
aliengrappler 1 year ago
Conclusion? Its impossible to be a person who
"only shaves ALL those who havent shaved themselves."
boorens18 2 years ago
Well, impossible to be a man from a village who only shaves those men of the village who do not shave themselves, yes.
It is P and not P at the same time if it was the case that the barber both shaved himself and not shave himself. A logical contradiction cannot exist, everything else is possible. It is not possible that this barber exists.
Hopefully applicable to a god that doesn't change ever (Malachi 3:6) and then does change often. (Exodus 32:14) (1 Samuel 15:35) Proof of nonexistence
gklr 2 years ago
There is no belief required to say this barber does not exist, excepting the axioms of logic itself. For what we can call true in any form, such as 1+1=2, it is raining out or it is not raining out (tautologous truth), or the sun is larger than the earth (empirical truth), we can show the gods of the bible and koran nonexistent. If existent is to mean anything at all, then those do not apply. That is why this video exists, to show how we prove something does not exist, no belief required.
gklr 2 years ago
Its too bad all gods cannot be shown to be P and not P at the same time the way christian and muslim gods can be. Then atheism would not be a belief at all.
Yet, to deny gods of deism, the heaven of buddhism (nirvana), Santa Claus, or the tooth fairy as existent requires a P and not P at the same time where I have not found one. So I'd say Santa Claus has a better chance of existing than the christian god does. This says nothing for atheism though, it is an anti-christian position itself.
gklr 2 years ago
Reindeer don't fly is valid, and if they did they would not be reindeer at all. So this aspect could dispell Santa and be a contradiction that the myth requires. But a myth is not a falsehood, it is not a "proven to not be", it is a myth because the only verification of it is the story itself. I could write a story right now about driving to work tommorow and seeing horses and today it is a myth, tommorow if it happens (and likely will) it is no longer a myth.
gklr 2 years ago
SO the barber is a man in a village
Does the barber shave himself if he only shaves men in the village who don;t shave themselves
So if the barber doesn;t shave himself, then he must shave himself
IF the barber shaves himself then he must not shave himself.
LOL, funny.
Theres only 1 possible conclusion from the definition given. All these people arguing over the answer, haha, funny.
sashajw1234 2 years ago
Another barber???
iDrowzee 2 years ago
I know this is a classic puzzle but it is flawed.
There is an assumption that the barber is an inhabitant of the village in question. In no variations that I've seen does it specifically say that the barber lives in that particular village. SO, the barber can exist if he is from a neighboring village.
Of course I've also read this statement were they don't say that the barber is a man. In that case of course the barber can exist if the barber is a female or a young boy.
sharkinfested 2 years ago
The point is to show how we demonstrate non-existence. And yes, the barber lives in the village.
there is no flaw, it is P and not P at the same time, proof of nonexistence.
gklr 2 years ago
@sharkinfested,
Easy fix. Just state that the barber lives in the village, that the barber is a man, and that he shaves all the men of the village. That closes the loopholes.
dmnemaine 11 months ago
@dmnemaine,
"Easy fix. Just state that the barber lives in the village, that the barber is a man, and that he shaves all the men of the village. That closes the loopholes. "
Then he does not shave all those men who do not shave themselves, as he would shave himself.
gklr 2 months ago
@gklr, I understand that. I was specifically responding to sharkinfested's comment. The "flaws" that shark pointed out are not really problems because they're easily remedied with a few words here and there.
dmnemaine 2 months ago
The barber can exist a couple ways. We know nothing about the barber other than that which we are told, that he shaves all those that don't shave themselves and that he ONLY shaves those that don't shave themselves.
There are people, both men and women, who are incapable of growing any body or facial hair, the barber could be one of them. Alternatively, the barber could have been tragically burned from head to toe, destroying all of his hair folicles. Let us not forget about NAIR.
Dreznin 2 years ago
If he does not grow hair, then he cannot shave himself, thus he does not shave all those men of the village that do not shave themselves.
gklr 2 years ago
@Dreznin,
A person who is incapable of growing body hair does not shave themselves; therefore, the barber in question shaves shaves that person because he shaves all those who do not shave themselves. Since that person is himself, he does not shave himself. The paradox still exists in that case, and the barber does not.
dmnemaine 11 months ago
A koan does not necessarily have one answer. To suggest that there is an either/or answer highlights the limitations of rock (Western) logic. Hara (Japanese) logic has more possibilities.
sumimahen 2 years ago
Obviously the barber cannot shave himself and cannot not shave himself. The barber cannot exist. I think this video went right over your head. You missed the point entirely.
gklr 2 years ago
Koan is nonsense and is not a field to be taken seriously or compared to formal logic. It is poetry at best, utter trash at worst.
When you think you can violate the law of the excluded middle, you are too wiped out of your head to be rational. simple.
gklr 2 years ago
Bertrand Russel would be appalled by the way gklr has reduced his paradox to an easily solvable riddle using classical "exluded middle" logic.
zencat 2 years ago
The question is, does the barber shave himself? In this form the contradiction is not very difficult to solve...I think it is clear that you can only get around it by observing that the whole question whether a class is or is not a member of itself is nonsense, i.e. that no class either is or is not a member of itself, and that it is not even true to say that, because the whole form of words is just noise without meaning. Bertrand Russell, The Philosophy of Logical Atomism
Idiot.
gklr 2 years ago
That quote shouldn't be making me the one who feels like an idiot, Greg. The Barber's Paradox didn't make as big a splash as it did because it's not difficult to solve with classical logic. It's just the starting point for discussing why logic alone is a flawed way to get to the truth, although you'd like it to be otherwise.
zencat 2 years ago
If that quote doesn't make you realize how idiotic your words were, then that is as funny as most of what you say. And besides, only through your misinterpetation have I said this boils down to the excluded middle rule. It is actually "P and not P, at the same time", which proves what cannot exist and the barber applies.
gklr 2 years ago
In quantum reality, the barber neither exists, nor does he not exist, for he is composed of 'stuff' that exhibits that same nature. And we are all barbers. ;-)
zencat 2 years ago
If so, then quantum reality is an utter loss. Clearly the barber cannot exist, there is no such possible barber. If a baby dies before it ever cut some hair, it was never a barber.
An object exists or not, there is no such possibie thing that is, and is not.
Perhaps zen buddhism is good for inspiring poetry, but clearly if that is the result of your inquiry into the world then I would use it as an example of why to avoid it. Utter nonsense. Quantum Quakery, not QM science. QM I respect.
gklr 2 years ago
You didn't read my comment correctly. I said an object neither exists nor does it not exist. No matter, this also violates your precious rules of logic, which you've admitted elsewhere cannot be proven beyond a doubt, and in spite of the fact that QM demonstrates that there are clearly conditions in which logic does not apply. You've succumbed to the same insanity that troubles theists- you've created a belief system from which you refuse to waver.
zencat 2 years ago
An object either exists or not. It is as impossible for this barber to exist as it is for anything to neither exist or not exist.
Quantum Quackery is not QM. You cite QQ, not QM. The laws of logic need to be assumed or there is nothing that can be said at all, including the poets.
Offer some reasoning as to how an object neither exists nor does not exist. Just reciting poetry isn't very informative.... and whatever logic you submit saying so, will clearly contradict itself.
gklr 2 years ago
Well, we agree here some, though not that poets need be logical. Logic and reason will not take you to the ground of reality, so you're right, there's nothing to be said, and I will surely contradict myself. But tell me, what words can be used to describe the taste of an apple, or the experience of sex, that will take the place of the experience itself? Yet clearly they are a part of reality, even if they are nothing more than someone else's dream.
zencat 2 years ago
Poets are not logical, nor need be. Contradicting yourself is the surest sign you are wrong.
gklr 2 years ago
Speaking of poetry, try this from Walt Whitman- "I contradict myself? Very well then- I contadict myself. I am large enough to contradict myself." Your left brain, linear mind will never see the truth in that, Greg. Dressing people down as quacks won't change the reality of what they see, and you do not. Sorry. Hostility is a sure sign of a deluded mind. Your godless world would be just as angry as this one, and far from righteous.
zencat 2 years ago
I pan "rightiousness" as deluded and even dangerous. Do-gooders are idiots. When I am not ragging on religion, I am ragging on those who think morality and ethics can be objective.
You are a quack because you think holding to contradictions is sensible. Whackjob material.
gklr 2 years ago
That's funny, Greg- you rag on those who think morality and ethics can be objective, yet you believe your opinions are absolutely and "objectively" correct. That's why you come off as self-righteous as any theist. You better start ragging on yourself! Righteousness lies beyond objectivity, in a reality you have yet to see. Of course, your ideas are quite easy to grasp, and are therefore quite popular. Enjoy your popularity, and your self-imposed bondage. A few of us whackjobs have found freedom.
zencat 2 years ago
That subjective opinion exists, provably and objectively, is not news. I do not say it is absolute because that would be silly after proving no absolute is possible.
You speak as poorly for me as you do Bertrand Rusell. Get your money back on those ESP lessons. lol.
gklr 2 years ago
This is more or less my point in commenting on your vids in the first place. Just think about that phrase, "...after proving no absolute is possible." Huh? You argue your "proofs" as though they ARE absolute. It colors your thinking and reasoning in ways you don't even realize. It doesn't take ESP to see that. When Russell was asked if he would die for his views, he responded, "Of course not- I could very well be wrong!" The implication is he probably wasn't willing to live by them, either.
zencat 2 years ago
That absolute truth is impossible, is itself a systemic truth, not an absolute one. It was not true before mind or language existed and could not have been. No truths existed then. No words, no statements existed then. Truth is a characteristic of a statement and only ever applies to statements. Again, you so misunderstand it is funny. If Russell or myself is wrong, show it. You don't even understand what is being said, so I won't hold my breath.
gklr 2 years ago
is it not, therefore the case, that the axiom which we begin with, ie, the barber shaves only the men who do not shave themselves, is not a denoting statement, like, russells example of the bald king of france. we can break this paradox down into 3 bits too, there is one man who is the barber, all the men who are the barber shave only the men who dont shave themselves, and the barber does not exist. so the 3rd premise is all that makes the barber impossible, not physical law. any of that ok? lol
feste121 2 years ago
The barber does exist, as long as the barber is a woman. That is it, problem solved. Think about it.
micoams 3 years ago
Wrong.
GKLR clearly sated that the barber was a man.
cgo11 3 years ago
lol.
There is a woman in a village who is a nail technician and who only does the nails of those women in the village who do not do their own nails. Does she do her own nails or not?
If she does, it cannot be true that she only does the nails of those women who do not do their own nails.
If she does not do her nails, then it is not true that she only does the nails of those women of the village that do not do their own nails.
No such woman could exist.
gklr 3 years ago
Agreed.
There is an endless number of such psuedo-paradoxes, includin Russell's paradox itself
cgo11 3 years ago
I see a comment that seems very similar to me but here's my answer anyways.
Basically you said this:
Barber only shaves men who don't shave themselves.
You did not say:
Barber shaves all men who do not shave themselves, but no men who shave themselves.
Your problem is only truely based on whether or not the barber shaves himself, not whether such a person could exist.
The barber himself certainly could exist.
LuminousXMI 3 years ago
Luminous,
The barber cannot exist because it cannot be true that the barber shaves himself and it cannot be true that the barber does not shave himself.
gklr 3 years ago
The paradox you seem to be so proud of is based on a rule that he cannot shave men who shave themselves. This barber can follow this rule quite simply, he needs only to not shave himself.
LuminousXMI 3 years ago
The barber shaves only all those men of the village who do not shave themselves. If he does not shave himself, then he does not shave all those men of the village who do not shave themselves, which was the description.
The barber cannot shave himself and be that description, and the barber cannot not shave himself and be that description, and so the barber cannot exist as per that description, shaving only all those men of his village that do not shave themselves.
gklr 3 years ago
Always does not apply, since nothing occurs always. Time applies, in that you cannot provide any time when it is possible that the barber shaves himself or does not shave himself, because if either is true then it cannot be the barber who lives in this village and only shaves those men of the village who do not shave themselves.
If yes, no barber.
If no, no barber.
No barber. He cannot exist, at any time.
gklr 3 years ago
woweeez,
The barber cannot exist because the barber cannot shave himself and cannot not shave himself. If he shaves himself, it is not true he shaves all those men who do not shave themselves. If the barber does not shave himself, it is not true he shaves all those men of the village who do not shave themselves.
There can be no such barber, sincet the barber cannot shave himself and cannot not shave himself.
gklr 3 years ago
let's call shaving others shaving and shaving oneself trimming. The barber shaves all who doesn't trim. Does the barber trim? No paradox here, though exactly the same question is put forth with a more specific vocabulary. The Barber may or may not trim (shave himself) when we recognise that shaving oneself is doing something different than shaving someone else. The premisses doesn't tell if he shave himself or not.
Censeo 3 years ago
Censeo,
The barber cannot exist. That is the point of the video. This video shows how to prove what does not exist, counter to the often heard argument that "We cannot prove a negative", which is nonsense.
If the barber shaves himself, he does not shave all those men of the village who do not shave themselves. If the barber does not shave himself, he does not shave all those men of the village who do not shave themselves.
The barber cannot exist.
gklr 3 years ago
Yes I can see that is what you try to argue. You didn't address my rebuttal, which is that shaving oneself and shaving someone else isn't the same form of action, and the paradox relies on the fact that two different actions has the same word.
Censeo 3 years ago
to do X to Y and to do X to Z is linguistically to do X sometimes though both things are completely different things (to shave Peter and to shave Roger are not to do the same thing). Sometimes it is not to do X linguistically even. (To have sex with Peter and to have sex with oneself is both not intercourse, one is masturbation). So we know that to shave someone and to shave yourself is two different kinds of actions.
Censeo 3 years ago
uhm isn't it that because it's a; THOSE men who don't shave them selves dousn't that rule NOT aply to the dude who is a barber???
so uuhm isn't that a solution?
robindesade 3 years ago
I missed that part,
but if you take out that line, then there is no contradiction and you can use that to prove that the barber cannot be not a member of the village; in other words, no village contains every barber.
bobdolz 3 years ago
or the barber is not a member of the village
bobdolz 3 years ago
There is a man who is a barber in a village...
gklr 3 years ago
I wouldn't be surprised if you get many more subscribers in the future.
You make your points very clear and back them up in the comments - not always a common thing on YT.
Canteatpancakes 3 years ago
I like the barbers paradox, when I first heard it I told it to my friends and we had a good time debating it :). Another paradox I like is the so called Monty Hall paradox, witch I learned about in a math class some years ago. I see you are an active atheist, posting debates to counter religion. I have no problem with that, however, I'm an atheist so I don't have to speculate about a god =) Keep it up.
Wrap1nol 3 years ago
Linguistic knot. It is still like the square circle though. This Barber isn't defined, because I have yet to understand what it means practically to shave oneself and not shave oneself. If that doesn't mean anything, then you haven't explained what this Barber is like.
Censeo 3 years ago
The barber is defined as a man who lives in a village and shaves only all those men of the village who do not shave themselves. If he shaves himself he cannot shave only all those men of the village who do not shave themselves. If he does not shave himself then he cannot shave only all those men of the village that do not shave themselves. There is no 3rd option, therefore the barber cannot exist. There is no such possible barber.
gklr 3 years ago
I don't know what it means to shave all those men who doesn't shave themselves, as I have trouble understanding if he shaves himself or not. So you haven't explained what kind of barber he is at all. It is exactly like saying square circle, or a barber who doesn't cut anyones hair or shave anyone ever. We know not what any of these concepts mean.
Censeo 3 years ago
The concepts are simple. There is a village with people, men live there. Of those men, one is a barber. He shaves people. He only shaves those men who do not shave themselves. Not shaving yourself means you do not take a razor and put it to your skin. Of those men who shave, they do put a razor to their skin to remove hair. There can be no such male barber, who shaves all the men of the barbers village who do not shave themselves. It can't exist.
gklr 3 years ago
The further necessary implications of a description is part of the concept. Therefore a non descriptive element is part of the original description. Therefore the original description describes nothing, or need to be clarified so that we understand the description.
Censeo 3 years ago
its easy to understand.... it's pure logic you don't need any other descriptions.
trisix99 3 years ago
It means:
The barber shaves a man if and only if he does not shave himself. For every man it is either true or false that he shaves himself and by the Axiom of Specificition there exists a subset of the members of the village that consists of all the men who do not shave themselves and no one else. This uniquely charactarizes the barber's actions but it does not guarantee his existence. The contradiction that follows proves his nonexistence.
bobdolz 3 years ago
There seems to be a hidden assumption:
All men must either shave or be shaven.
If the barber simply lets his beard grow, then he can exist. So: Either he does not exist, or if he exists, he has a very long beard.
Cimbolic 3 years ago
"There seems to be a hidden assumption:
All men must either shave or be shaven."
Yes, it is the law of the excluded middle, introduced by Aristotle and one of the laws of logic. Every proposition is either true or false, there can be no middle. While we can believe what we want, what we believe doesn't itself show a truth.
If the barber simply lets his beard grow, then he does not only shave all those men of the village who do not shave themselves.
gklr 3 years ago
I see. He would not be shaving them "all" because there would be one he does not shave (himself). Excellent. I knew this conclusion would crumble, glad you found the flaw.
Cimbolic 3 years ago
Actually I made a mistake there.
"All men must either shave or be shaven" is not the law of the excluded middle. All men must either shave or not shave, is. All men of the village are either members of the set of those who shave themselves or members of the set of those men who do not shave themselves. "Shave or be shaven" isn't that. The assumption is that every man shaves himself or not. My error.
gklr 3 years ago
I one time went to the mall. Jesus was a Jew. The barber is a hog, that is why he shaves his mother. It's not a paradox i just figured it out!!!
trooperman4 4 years ago
A singular insight, trooperman4. :-)
Cimbolic 3 years ago
this paradox....shall be put to good use.
DeadMindWorking 4 years ago
the barber shaves the man in the mirror
superfisto 4 years ago
I am interested in your responce to another 'interesting' logical problem:
(1) the number of planets is 9.
(2) It is necessay that 9>7.
(3) therefore, it is necessary that the number of planets is greater than 7.
Clearly the premisses are true and the conclusion is false.
Why is this logic faulty?
cgo11 4 years ago
Your analysis is correct.
There are at least two other logical proofs that this barber cannot exist.
e.g. ~EyAz(y shaves x iff ~(x shaves x) is a theorem of logic.
(the x: x shaves all and only those that do not shave themselves) is not unique.
Owenholden 4 years ago
The answer to Russell's question, does the barber shave himself, is no!
There are no things that non-existent things can do.
Owenholden 4 years ago
I tried my best (oh goodness I did) to come up with a good reply to this. My brain is still frazzled by it. I'm looking forward to the next one... heck I am looking forward to continue this exploration.
Papamaru70 4 years ago
He doesn't. He goes to an other barber in a next village
vadiku 4 years ago
This is similar to the Liars Paradox. If a person says "I am Liar." Is he telling the truth, or not?
earlyphilosophy 4 years ago
gklr, or anyone that hasn't read it: pick up "A Brief History of the Paradox: Philosophy and the Labyriths of the Mind," by Roy Sorensen. You'll love it.
azrienoch 4 years ago
GK, I take great offense to your video. I am the barber of which you speak. I live in the village of Farada, but I am the barber to barundi. While I was in barundi a gentleman requested that I cut his wifes hair, to which I replied I only shave the heads of all the men who do not shave their own. I do shave my own head, and although this gentlemen's description of me is confusing because of the lack of context, I do not appreciate you denying my existence. It is bad for my business!
rUTokKIN2ME 4 years ago
You're right, that's fun. Please keep them coming.
ikamoj 4 years ago
Hah! Kirk and Spock could use this to save the entire galaxy from a hostile computer.
Elvisdogg 4 years ago
Thanks for that little gem Greg. Good to see you on here.
I hope to see more of you when you have time.
- Paul
pdoeman 4 years ago
That's great. I'm in a Language Proof and Sybolic Logic class right now.. are you a professor or something?
shibumi81 4 years ago
No I am no professor, just a fan of the genre. :)
gklr 4 years ago
That's a nice little paradox there. Keep 'em coming.
Balphaus 4 years ago