Randy Souther wrote:
Why don't you just ask them if it is dark or not?
Randy
Horace was providing the solution to the "classic" riddle, which goes something like this:
"One tribe lies, the other doesn't; one has red feet, the other green; you don't know which is which; on a dark night how do you determine the color of a native's feet with one question?"
The riddle as stated was a little different and included the information as to which color of feet went with lying (most likely by mistake) and in consequence it had, as one obvious solution, the question "Is it dark out?". That doesn't solve the classic version, however.
If they can "lie to themselves" while telling the truth to an outsider then the answers they give are effectively random and it can't be solved just by asking a single question.
On Jan 10, 2005, at 11:47 PM, Horace Heffner wrote:
At 10:29 PM 1/10/5, RC Macaulay wrote:
BlankYa havta love this group!! Stephen Lawrence is correct in his view.. but.. think again of the question.
The red foot tribe never lies and the green foot tribe never tells the truth
The question presupposes an attempt by the visitor to determine if the
tribe is red foot or green foot using the knowledge of their respective
traits of lying or telling the truth by the color of their feet. The lying
green foot could answer yes and be lying to himself .
It is easy to tell who is whom, even if they will only answer yes or no,
provided the red foot tribe never lies and the green foot tribe never tells
the truth, and assuming of course you get an answer.
The question for yes or no answers is: "If I asked the other tribe in the
region if their feet are red, what would they say"?
The response will always contain a single lie.
If the response is yes, then the true answer is no. The other tribe has green feet, thus never tells the truth. The tribe answering has red feet and always tells the truth.
If the response is no, then the true answer is yes. The other tribe has
red feet, thus never tells lies. The tribe answering has green feet and is
always lying.
Now, if the green foot lies to himself and thereby tells the truth, this
denies the fundamental premise of the problem that the green foot tribe
never tells the truth. The problem is then merely nonsense. Might as well
pretend they are all senile. If the green foot tribe in fact never tells
the truth, and the red foot tribe never lies, and they know a simple
fundamental fact like which tribe is which, then the problem is meaningful
and it is easy to tell which tribe is present with one yes or no question.
Regards,
Horace Heffner
