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There is a kingdom where if a person drinks poison he will die. The

  1. Aug 31, 2012 #1
    There is a kingdom where if a person drinks poison he will die. The only way to counteract the poison is to drink a stronger one. Then the reaction stops. The king decides that he must have the strongest poison available in his possession. So, he sets up a contest between his court adviser and his wizard. Each must find the strongest poison in the kingdom and give it to him. But to be sure that he will get the strongest poison, he will force each to first drink the others' poison. Then they will drink their own. One of them will die, but the king will certainly then have the strongest poison in his possession.

    The court adviser knows that he can never outsmart the wizard, and bemoans the fact that in a few days time he will die. But soon, he and his wife think of a plan to outsmart the wizard.

    The day of the contest arrives. The wizard drinks the advicer's poison, and vice-versa. Then they drink their own and the wizard dies.

    What was the advicer's trick?
  2. jcsd
  3. Aug 31, 2012 #2
    Re: Functions.

    Dear Sir,
    It is taken from a book, Advanced Mathematical Thinking. The question given to novice and expert in mathematics. The author said even some of the interviewees said it wasn't mathematics.

    That's the reason why I'm posting it here to see where the subject of function is relevant.
    Last edited: Aug 31, 2012
  4. Aug 31, 2012 #3


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    Re: Functions.

    The adviser's poison wasn't poison. Sadly, though, it means both die, so it was something of a Pyrrhic victory.
    I can roughly think how to express this in terms of functions, but not in a way that makes the answer any more obvious. Maybe I don't have the best answer.
  5. Aug 31, 2012 #4
    Re: Functions.

    After half a day of thinking, i think got the answer.
    The author mention about reversal tactic.
    He makes example of a volume and if we reverse it, we will see a curve that rotates around an axis.
    In mathematics according to author, the process of forward and reversal "function" is common example differentiation and intergration.

    Here the wizard is dead due to his less poisonous potion-forward.
    So the trick is to make the strongest poison-reversed.
    Last edited: Aug 31, 2012
  6. Aug 31, 2012 #5
    Re: Functions.

    There is a branch of maths/logic where this properly belongs, but I don't see it as a theory of functions issue.

    I suggest you approach one of the maths mods to move this to the logic forum and ask about predicate logic.
  7. Sep 1, 2012 #6


    Staff: Mentor

    Re: Functions.

  8. Sep 1, 2012 #7


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    Staff: Mentor

    Re: Functions.


    Without any functions, unless you want to define a "poison strength function":
    The court adviser knows that the wizard will come up with a poison W stronger than anything he can do. This is a lower limit for the strength of the wizard's poison. Now, he collects poison C, which is than this limit.
    Before they meet again, he drinks C, and in the meeting he presents water as his best poison. He has to drink W, which cancels the poison he drank in advance. He then drinks water, and survives. The wizard, assuming he just made a very strong poison, first drinks water and afterwards his own poison, and dies.
    Maybe more peaceful: The court adviser presents a weak poison as "his strongest poison", and heals himself with a stronger poison afterwards. Both survive.
    Both plans can fail if the wizard plans something similar.
  9. Sep 1, 2012 #8
    Re: Functions.

    Here the author's explanation.
    Sorry for my bad English.
    Anyway it was taken from a chapter on Function.

    It is the sequence of drinking that kills the wizard.
    It means the wizard drank the strongest poison(adviser) then his less poison- this is the data.
    And the adviser drank wizard's less poison and finally his strongest poision-data too.

    It is shown that above sequence produced the outcome.
    Just like as the author says about a volume, sequence of curve and rotation.
    Last edited: Sep 1, 2012
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