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#1 Re: Puzzles and Games » The Professor and the Student » 2013-12-16 20:47:40

I thought this was totally sorted by Bob Bundy.  Maybe he wasn’t clear enough so I’ll have a go for him.

Let’s call the test availability period,  TAP, measured in days. 

The professor has declared:  Statement   = “…but you won't know in advance which”

So on Sunday evening,


As we reach the evening of each day without a test,  TAP reduces by 1 and if we count back one day TAP increases by 1.

Deduction one:  So by Thursday evening

   and so the student deduces that the statement implies  the test cannot take place on Friday, so

So far, so good.  But then the student’s logic goes wrong.  The student’s logic, not the professor’s.  Which is at it should be; he is the professor after all.  :)

On Wednesday evening

  .  But the student thinks
  because of deduction one and counting back one day.   And hence the test cannot take place on Wednesday, making

But  you cannot use deduction one on Wednesday evening , because deduction one requires that it is Thursday evening  and it isn’t.  You cannot use logic like this.

In post 56 Bob set up a parallel situation involving his next post.  In post 65 he made this post.  No one successfully predicted when he would post, but the post occurred.  He clearly wasn’t lying!

He also said he was giving up on the thread thereafter.  That’s why he has asked me to remind everyone about what he said; so he can maintain the position that he was not lying.  

I am, of course, happy to assist him.  smile

Alta ego

#2 Re: Puzzles and Games » The Professor and the Student » 2013-05-04 05:51:35

Agnishom wrote:

Ai do not mean to be rude, but I doubt your identity…

What do you mean?  I am who I am.  I recommend you re-read posts 57 and 66.


#4 Help Me ! » what does this become? » 2012-12-15 09:59:59

alta ego
Replies: 1

Can somebody help me do


#5 Re: Puzzles and Games » The Professor and the Student » 2012-03-30 09:34:33

hi guys,

You seem to be missing something.

In post 57 bob said he would post during the week but you wouldn't know when.

In post 66 he posted.  It was a Tuesday.  Nobody predicted that.

He also said "So, I'll have one last go and then I'm giving up on this thread."

So he is clearly not going to come back to this thread again.

Case closed.

alta ego

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