Jump to content


Welcome to BrainDen.com - Brain Teasers Forum

Welcome to BrainDen.com - Brain Teasers Forum. Like most online communities you must register to post in our community, but don't worry this is a simple free process. To be a part of BrainDen Forums you may create a new account or sign in if you already have an account.
As a member you could start new topics, reply to others, subscribe to topics/forums to get automatic updates, get your own profile and make new friends.

Of course, you can also enjoy our collection of amazing optical illusions and cool math games.

If you like our site, you may support us by simply clicking Google "+1" or Facebook "Like" buttons at the top.
If you have a website, we would appreciate a little link to BrainDen.

Thanks and enjoy the Den :-)
Guest Message by DevFuse
 

Photo
- - - - -

Mad Hatter question


Best Answer witzar , 29 March 2013 - 12:28 PM

Spoiler for

Go to the full post


  • Please log in to reply
14 replies to this topic

#11 bonanova

bonanova

    bonanova

  • Moderator
  • PipPipPipPip
  • 5841 posts
  • Gender:Male
  • Location:New York

Posted 29 March 2013 - 06:51 PM

Spoiler for

 

A new approach. Works for me.


  • 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#12 Yoruichi-san

Yoruichi-san

    "That Woman"

  • Members
  • PipPipPipPip
  • 3394 posts
  • Gender:Not Telling
  • Location:Outside the box

Posted 29 March 2013 - 07:50 PM

*Clears throat*

 

Spoiler for In case it wasn't obvious earlier...

 

It's similar to bon-chan's approach of setting up a logical question that cannot be answered by a simple yes/no for one of the doors.


  • 0
Women are definitely stronger. We are [Fe]males, after all...

Some of what makes me me is real, some of what makes me me is imaginary...I guess I'm just complex. ;P

<3 BBC's Sherlock, the series and the man. "Smart is the new sexy."

Chromatic Witch links now on my 'About Me' page! Episode 3 is finally here!

When life hands me lemons, I make invisible ink.

#13 bonanova

bonanova

    bonanova

  • Moderator
  • PipPipPipPip
  • 5841 posts
  • Gender:Male
  • Location:New York

Posted 30 March 2013 - 04:15 AM

*Clears throat*

 

Spoiler for In case it wasn't obvious earlier...

 

It's similar to bon-chan's approach of setting up a logical question that cannot be answered by a simple yes/no for one of the doors.

 

I'm not sure he poofs for the left door.

 

In your logic does F -> anything?

I was not sure that he could not say Yes or No, with equal validity if it were the leftmost door.

 

That is, A -> B can be taken to be ^A v B: F implies anything, and anything implies T.

So for the leftmost door and A = "there is at least one door to the left of the correct door"

your question is If A then are there 2 doors left of the correct door.

A being false, can't the answer be Yes or No instead of "I can't answer because the premise is false"?

 

The only approach is to force a Yes/No/Can't answer response, agreed.

 

Explanation for F -> T to be legit:

 

If 2+2=5 then New York is a small city.

In every case where 2+2=5 New York is a small city.

But there are no cases where 2+2=5.

Thus: In no case is New York a small City.

 

The only prohibited conditional is T -> F. the other three are OK. No?


  • 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#14 Yoruichi-san

Yoruichi-san

    "That Woman"

  • Members
  • PipPipPipPip
  • 3394 posts
  • Gender:Not Telling
  • Location:Outside the box

Posted 04 April 2013 - 06:53 PM

Okay, he might not poof, but he can't answer either, and a non-answer is an answer ;P.  My logical setup was not F->T, it was F->no longer a simple yes/no question.  Your example is a case where the premise is always false, in which case the statement itself has no inherent meaning and therefore you can manipulate it as you will.  The question I used I posed is either true or false, in the case it is true, it is a yes/no question, but if the first part is false, then it is not a yes/no question.

 

I.e. if I asked you:

 

If you are going on vacation this month, are you going leaving for more than a week?

 

If the first part is true, then it is a simple yes/no question.  If it is not, you would answer with, like, "I'm not going on vacation this month" or sth.  If you answered yes or no, it would indicate you are going on vacation this month.


  • 0
Women are definitely stronger. We are [Fe]males, after all...

Some of what makes me me is real, some of what makes me me is imaginary...I guess I'm just complex. ;P

<3 BBC's Sherlock, the series and the man. "Smart is the new sexy."

Chromatic Witch links now on my 'About Me' page! Episode 3 is finally here!

When life hands me lemons, I make invisible ink.

#15 bonanova

bonanova

    bonanova

  • Moderator
  • PipPipPipPip
  • 5841 posts
  • Gender:Male
  • Location:New York

Posted 06 April 2013 - 05:52 PM

Okay, he might not poof, but he can't answer either, and a non-answer is an answer ;P.  My logical setup was not F->T, it was F->no longer a simple yes/no question.  Your example is a case where the premise is always false, in which case the statement itself has no inherent meaning and therefore you can manipulate it as you will.  The question I used I posed is either true or false, in the case it is true, it is a yes/no question, but if the first part is false, then it is not a yes/no question.
 
I.e. if I asked you:
 
If you are going on vacation this month, are you going leaving for more than a week?
 
If the first part is true, then it is a simple yes/no question.  If it is not, you would answer with, like, "I'm not going on vacation this month" or sth.  If you answered yes or no, it would indicate you are going on vacation this month.


But if he could answer anything, he could answer yes; and you might not get home.
  • 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users