Paradoxes

[wild_goat_14]

What are your favorite paradoxes? Paradoxes always fascinated me when I was younger and it still does now, because I love how it makes you think. Here's an old favorite of mine, called the grandfather paradox.

 

 

 

A baby girl is mysteriously dropped off at an orphanage in Cleveland in 1945. "Jane" grows up lonely and dejected, not knowing who her parents are, until one day in 1963 she is strangely attracted to a drifter. She falls in love with him. But just when things are finally looking up for Jane, a series of disasters strike. First, she becomes pregnant by the drifter, who then disappears. Second, during the complicated delivery, doctors find that Jane has both sets of sex organs, and to save her life, they are forced to surgically convert "her" to a "him." Finally, a mysterious stranger kidnaps her baby from the delivery room.

 

 

 

Reeling from these disasters, rejected by society, scorned by fate, "he" becomes a drunkard and drifter. Not only has Jane lost her parents and her lover, but he has lost his only child as well. Years later, in 1970, he stumbles into a lonely bar, called Pop's Place, and spills out his pathetic story to an elderly bartender. The sympathetic bartender offers the drifter the chance to avenge the stranger who left her pregnant and abandoned, on the condition that he join the "time travelers corps." Both of them enter a time machine, and the bartender drops off the drifter in 1963. The drifter is strangely attracted to a young orphan woman, who subsequently becomes pregnant.

 

 

 

The bartender then goes forward 9 months, kidnaps the baby girl from the hospital, and drops off the baby in an orphanage back in 1945. Then the bartender drops off the thoroughly confused drifter in 1985, to enlist in the time travelers corps. The drifter eventually gets his life together, becomes a respected and elderly member of the time travelers corps, and then disguises himself as a bartender and has his most difficult mission: a date with destiny, meeting a certain drifter at Pop's Place in 1970.

 

 

 

The question is: Who is Jane's mother, father, grandfather, grand mother, son, daughter, granddaughter, and grandson?

 

 

 

That was entertaining to read. Too bad we can't travel through time.

[Dullmage]

That Monty Hall door problem is not really correct, its just the way you write it out. I could say:

 

You switch doors to car, get it

 

You stay at yours, which is a goat

 

You switch doors to goat 1, get it

 

You stay at yours, which is a car

 

You switch doors, get goat 2

 

You stay at yours, which is a car

[tintin113]

That Monty Hall door problem is not really correct, its just the way you write it out. I could say:

 

You switch doors to car, get it

 

You stay at yours, which is a goat

 

You switch doors to goat 1, get it

 

You stay at yours, which is a car

 

You switch doors, get goat 2

 

You stay at yours, which is a car

 

 

 

Yea see that's because you obviously don't understand the key point, and thus have written it out wrong. The whole point is that the quizmaster or whoever knows which door the goat/car is behind and always removes at goat. However I've explained this problem to so many people now I really can't be bothered any more.

[Skull]

That Monty Hall door problem is not really correct, its just the way you write it out. I could say:

 

You switch doors to car, get it

 

You stay at yours, which is a goat

 

You switch doors to goat 1, get it

 

You stay at yours, which is a car

 

You switch doors, get goat 2

 

You stay at yours, which is a car

 

 

 

Yea see that's because you obviously don't understand the key point, and thus have written it out wrong. The whole point is that the quizmaster or whoever knows which door the goat/car is behind and always removes at goat. However I've explained this problem to so many people now I really can't be bothered any more.

 

I'll do it.

 

 

 

So you're starting off and you pick a random door. Now since there's 3 doors and one is a car and two are goats that means your chances of picking the car first guess is 33% and picking a goat is 66%. Now say you pick a goat the first time, since there's a better chance of that happening. The host has to reveal a goat, but since you already picked a goat there's only one door he can open up to show a goat. Because of this if you switch doors, the only thing you could switch to is the car. That means that your chances of getting a car are 66% if you switch to the other door. The point isn't that you get a car if you switch, it simply increases the chance of getting a car. You could pick the car to begin with but there's a greater chance that it will be a goat and in turn, a car when you switch it.

 

 

 

I hope that didn't confuse you more, the video near the beginning of the thread explains it pretty well I think.

[Zierro]

My favorite paradox has to be the Ship of Theseus paradox. The Tin Man in The Wizard of Oz is a prime example of this.

 

 

 

I don't really get that one. Human beings constantly recycle our cells, does that make us a different person?

[Dullmage]

Looking back, my post doesn't really make sense. I think I finally understand... When you originally pick, its only 33% you have picked the car and 66% the goat. When the host reveals one of the goats, you haven't learned anything new, since you knew at least one of the other doors must contain a goat. You will pick a goat 66% of the time originally, and theres only one door left, which is only 33% the other goat. It can only be a goat or a car, so 66% it is a car. Am I on the right track here?

[Nero]

Looking back, my post doesn't really make sense. I think I finally understand... When you originally pick, its only 33% you have picked the car and 66% the goat. When the host reveals one of the goats, you haven't learned anything new, since you knew at least one of the other doors must contain a goat. You will pick a goat 66% of the time originally, and theres only one door left, which is only 33% the other goat. It can only be a goat or a car, so 66% it is a car. Am I on the right track here?

 

http://en.wikipedia.org/wiki/Monty_Hall_problem

 

 

 

Also,

 

Pinocchio saying "This sentence is a lie"

[frakir_staer]

What are your favorite paradoxes? Paradoxes always fascinated me when I was younger and it still does now, because I love how it makes you think. Here's an old favorite of mine, called the grandfather paradox.

 

 

 

A baby girl is mysteriously dropped off at an orphanage in Cleveland in 1945. "Jane" grows up lonely and dejected, not knowing who her parents are, until one day in 1963 she is strangely attracted to a drifter. She falls in love with him. But just when things are finally looking up for Jane, a series of disasters strike. First, she becomes pregnant by the drifter, who then disappears. Second, during the complicated delivery, doctors find that Jane has both sets of sex organs, and to save her life, they are forced to surgically convert "her" to a "him." Finally, a mysterious stranger kidnaps her baby from the delivery room.

 

 

 

Reeling from these disasters, rejected by society, scorned by fate, "he" becomes a drunkard and drifter. Not only has Jane lost her parents and her lover, but he has lost his only child as well. Years later, in 1970, he stumbles into a lonely bar, called Pop's Place, and spills out his pathetic story to an elderly bartender. The sympathetic bartender offers the drifter the chance to avenge the stranger who left her pregnant and abandoned, on the condition that he join the "time travelers corps." Both of them enter a time machine, and the bartender drops off the drifter in 1963. The drifter is strangely attracted to a young orphan woman, who subsequently becomes pregnant.

 

 

 

The bartender then goes forward 9 months, kidnaps the baby girl from the hospital, and drops off the baby in an orphanage back in 1945. Then the bartender drops off the thoroughly confused drifter in 1985, to enlist in the time travelers corps. The drifter eventually gets his life together, becomes a respected and elderly member of the time travelers corps, and then disguises himself as a bartender and has his most difficult mission: a date with destiny, meeting a certain drifter at Pop's Place in 1970.

 

 

 

The question is: Who is Jane's mother, father, grandfather, grand mother, son, daughter, granddaughter, and grandson?

 

 

 

This is a Heinlein story: -All You Zombies-

[Wizz]

My favorite paradox has to be the Ship of Theseus paradox. The Tin Man in The Wizard of Oz is a prime example of this.

 

 

 

I don't really get that one. Human beings constantly recycle our cells, does that make us a different person?

 

The Paradox clashes with our idea of Identity. Is something still the same if we change it progressively, if so it wouldn't make a difference if we switch it all together in one go?

[Plugpoint]

I just read through all 12 pages, my head hurts... :roll:

[deathdrow]

Paradoxes are awesome, and I just realized pureprayer is banned. o:

[issy2]

Toast always falls on the buttered side, yes?

 

Cats, always on their paws?

 

Sorry, I had to.

 

 

 

 

 

About the buttered toast thing... my dad was telling me about this lecturer who was demonstrating Murphy's Law; for those who don't know, it states: if anything can go wrong, it will. If it can't go wrong, it will go wrong anyway. In front of a large audience this lecturer made some toast and buttered it, then dropped it on the floor.

 

The point is, whichever way it lands, he proves himself right. If it lands butter-side down, hooray, Murphy's Law's true. If it lands butter side up, the one time he wanted it to land butter side down it didn't. :P Brilliant, no?

 

 

 

And I'm not sure if this constitutes a paradox, and I'm sure a lot of people will already know this, but anyway - Three people go into a restaurant and order meals. Their total bill comes to £30. They decide to pay equally and each pay with a £10 note, which the waiter takes. However for some reason the maitre d' asked for them to be reimbursed £5, and gives the waiter £5 to return to the table. This £5 is in pound coins, and so the waiter realises they won't be able to split it equally. So he pockets £2 for himself and returns £3 to the table. Each of the customers take a pound coin.

 

So each customer originally paid 10, was given back 1, therefore they paid £9 each - a total of £27. The waiter took £2 for himself - where did the other pound go?

[brunokiller]

What are some of your favorite paradoxes?

 

 

 

I like "Proof that all numbers are equal"

 

Multiplying any number by 0 gives an answer of zero. For example

 

2*0 = 0

 

Rearranging the equation gives

 

2=0/0

 

However, by the same reasoning

 

1*0 = 0

 

1 = 0\0

 

and since

 

0\0 = 0\0

 

substitution gives

 

2 = 1

 

Before you divide both side of the equations by a certain number, you must always prove that number isn't zero.

[Guest User]

Toast always falls on the buttered side, yes?

 

Cats, always on their paws?

 

Sorry, I had to.

 

 

 

 

 

About the buttered toast thing... my dad was telling me about this lecturer who was demonstrating Murphy's Law; for those who don't know, it states: if anything can go wrong, it will. If it can't go wrong, it will go wrong anyway. In front of a large audience this lecturer made some toast and buttered it, then dropped it on the floor.

 

The point is, whichever way it lands, he proves himself right. If it lands butter-side down, hooray, Murphy's Law's true. If it lands butter side up, the one time he wanted it to land butter side down it didn't. :P Brilliant, no?

 

 

 

And I'm not sure if this constitutes a paradox, and I'm sure a lot of people will already know this, but anyway - Three people go into a restaurant and order meals. Their total bill comes to £30. They decide to pay equally and each pay with a £10 note, which the waiter takes. However for some reason the maitre d' asked for them to be reimbursed £5, and gives the waiter £5 to return to the table. This £5 is in pound coins, and so the waiter realises they won't be able to split it equally. So he pockets £2 for himself and returns £3 to the table. Each of the customers take a pound coin.

 

So each customer originally paid 10, was given back 1, therefore they paid £9 each - a total of £27. The waiter took £2 for himself - where did the other pound go?

 

 

 

Silly foreign money confusing me.. But in terms of US Dollars..

 

$10 + $10 + $10 = $30 total bill

 

Bill is reduced to $25. You now have $5 extra.

 

$2 is pocketed and $3 is returned.

 

So $25 bill + $2 tip + $3 returned = $30 original dollars.

 

 

 

The extra dollars was lost in the incorrect math of the riddle.

 

 

 

The riddle does.. 9+9+9=27, 27+2=29, 29=/=30

 

Each customer paid $9. The waiter has $2. The bossman has $25. So 9+9+9=27=25+2 or the total amount paid.

 

 

 

The tip should not be added to how much the customers paid, or the $27, but rather to the deposit they made of $25.

[michel555555]

A person wants to find out about a part of history that has not been recorded so he goes back in time and durring this he *changes* a part of history by killing a person, plant, animal whatever. does he actually manage to change history?

[Guest User]

What are some of your favorite paradoxes?

 

 

 

I like "Proof that all numbers are equal"

 

Multiplying any number by 0 gives an answer of zero. For example

 

2*0 = 0

 

Rearranging the equation gives

 

2=0/0

 

However, by the same reasoning

 

1*0 = 0

 

1 = 0\0

 

and since

 

0\0 = 0\0

 

substitution gives

 

2 = 1

 

You can't divide by zero.

 

 

 

A person wants to find out about a part of history that has not been recorded so he goes back in time and durring this he *changes* a part of history by killing a person, plant, animal whatever. does he actually manage to change history?

 

Nope. Reminds me of the movie Deja Vu. By trying to change the future, one causes it to occur.

[michel555555]

edit- nevermind

[ontarget1]

its impossible to go back in time to alter anything.

 

if you went back in time to stop world war 2 world war 2 would of never happened. but then there wouldnt be a reason for you going back in time so that version of you would fade out of existance. then because you don't exist world war 2 would still hapen which means you do exist meaning ww2 didnt happen causing you to not exist meaning nothing stops ww2 from happening so you exist again so ww2 didnt happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ARGH MY HEAD! AVE ME CHUCK NORRIS! AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!! *universe implodes*

[darksonic45]

its impossible to go back in time to alter anything.

 

if you went back in time to stop world war 2 world war 2 would of never happened. but then there wouldnt be a reason for you going back in time so that version of you would fade out of existance. then because you don't exist world war 2 would still hapen which means you do exist meaning ww2 didnt happen causing you to not exist meaning nothing stops ww2 from happening so you exist again so ww2 didnt happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ww2 did happen that means ww2 didnt happen which means ww2 did happen which means ARGH MY HEAD! AVE ME CHUCK NORRIS! AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!! *universe implodes*

 

I think my brain exploded.

 

 

 

The time travel thing has given me a huge amount of various ideas but here's 3 of my basic thoughts.

 

 

 

1. Change the past, change the future

 

2. Change the past, it causes whatever happened in the future. Future is written in stone.

 

3. Every second there is an infinite amount of new universes born from the various different choices made.

[Sbrideau]

Actually, if you go back in time, I belive you end up in a different universe :o

[Will H]

A person wants to find out about a part of history that has not been recorded so he goes back in time and durring this he *changes* a part of history by killing a person, plant, animal whatever. does he actually manage to change history?

 

I suppose the many worlds theory fixes this. Imagine that every single possible timeline is manifested as a world, which I suppose would be an infinite number. To simplify, imagine two such worlds, one where a war happened in the past with no influences, and one where a passing time traveller stopped the war from happening.

 

 

 

Okay, so the time traveller, being in the first world, knowing that the war happened, jumps in his time machine. The machine arrives with no problem, but as soon as the war is prevented, the traveller has created a new world, and follows the new timeline. The traveller could now move forward in time to a future where the war never happened, and may possibly meet an alternate version of himself if that is part of the new timeline, with no paradoxes. The war happened, and it didn't happen, depending on your frame of reference. Three cheers for special relativity.

[tintin113]

Actually, if you go back in time, I belive you end up in a different universe :o

 

 

 

This. Every "moment" in time creates a new universe.

[Mollerz]

a=b

 

a^2=ab

 

2a^2=a^2+ab

 

2a^2-2ab=a^2+ab-2ab

 

2a^2-2ab=a^2-ab

 

2(a^2-ab)=1(a^2-ab)

 

2=1

 

 

 

Let's go through this step by step.

 

 

 

a=b Start

 

a^2=ab (times whole equation by a)

 

2a^2=a^2+ab (what the hell did you do here? You timesd the left side of the equation by a^2 and you added a^2 to the right hand side. You fail. It should be 2a^2=ba^3)

 

 

 

He added, not multiplied.

 

Since a=b, you can look at the second to last step and replace the (a^2-ab) with (a^2-a^2). That equals 0, so you're basically taking 2(0) = 1(0), which is true.

 

 

 

I actually go back on what I said originally. That was really [developmentally delayed]ed. I guess I am used to seeing it as a² rather than a^2 and misinterpreted it somewhere. (By the way if you want ³ or ² then use alt codes Alt+0179 and Alt+0178).

 

 

 

           a = b

         a² = ab

        2a² = a² + ab

  2a² - 2ab = a² + ab - 2ab

  2a² - 2ab = a² - ab

 2(a² - ab) = 1(a² - ab)

 

 

 

There it is for those who like it like I do.

[Will H]

Actually, if you go back in time, I belive you end up in a different universe :o

 

 

 

This. Every "moment" in time creates a new universe.

 

Not just one, infinitely many, because there's an infinite number of things that could happen (although they would all be highly improbable) between one moment and the next. The multiverse isn't just infinite, it's insanely infinite.

[OwnagePie]

I found this one lets see if anyone can solve it:

 

 

 

Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?

 

 

 

Yes. You have a 1/3 chance of getting it in the 1st place, and a 1/2 after the 1st door. However, once he asks, that changes everything (aka variable oods). If you say yes, ill change, you'll have a 66% chance of winnning.

 

 

 

Cookies to who figure outs what thats from :XD:

 

 

 

The movie 21.