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SPOILER ALERT (ANSWER OF RIDDLE BELOW): I don't really see where you got stuck. Could you mind explaining me why/how/where you got stuck? I couldn't find a sat

SPOILER ALERT (ANSWER OF RIDDLE BELOW): I don't really see where you got stuck. Could you mind explaining me why/how/where you got stuck? I couldn't find a satisfying 'aha!' moment so I just kind of brute forced all the possibilities ..

mbell 12y ago
I got it wrong, not due to lack of logic but due to lack of spending the time to untangle the strange wording. I read it as "Jack is looking at Anne, but Anne is looking at _Jack_." and assumed it was some sort of trick question. If they were really interested in testing logic they would deliver the problem in a clear manor rather than masking it strange wording.
lkrubner 12y ago
SPOILER ALERT (ANSWER OF RIDDLE BELOW): Like most people, my first thought was c. And yet, as I said, I suspect that if this had been presented as a bit of Java or Ruby, I would have been unlikely to make that mistake. I read English with a laziness that is different from how I read computer code.
- deleted 12y ago
  [deleted]
gjm11 12y ago
The failure mode isn't getting stuck, it's failing to notice that there's actual work to do. The way you get this one wrong is a thought process like this: "Well, obviously we only know about the first and third links in the chain, and we aren't told anything about the second one. So of course we can't tell whether there's a married person looking at an unmarried one because we have no information about any two directly 'connected' people." (But less explicit -- if you think about it in that much detail you're likely to think of brute-forcing the possibilities.) Or like this: "Well, let's see: A looks at B looks at C, A is married, C not. Does A->B have to be married->unmarried? No; B could be married. Does B->C have to be married->unmarried? No; B could be unmarried. So we're done." Once it occurs to you that you could just kind of brute force all the possibilities, you're going to get it right. The problem comes when you short-circuit the process. (And the reason why doing so isn't just stupid is that often this sort of "pruning" of mental effort is key to working things out efficiently. It just happens that in this case the prunability is illusory.)
- Double_Cast 12y ago
  To expand on this. At first glance, we don't know what value Anne has. But marital status is a boolean value. Since marital status is boolean, it follows by the Law of the Excluded Middle that Anne is either {married | unmarried}. If we brute force the question by simulating each possible value that Anne can assume (and follow the implications), we arrive at the correct answer. But imagine a case where we test for flavors of ice cream rather than marital status. > Jack is looking at Anne, but Anne is looking at George. Jack has chocolate ice cream, but George has vanilla ice cream. Is a person with chocolate ice cream looking at an person with vanilla ice cream? Can we correctly answer the new question? No, because Anne might have strawberry ice cream. A flavor isn't a boolean value! Also consider that simulation (especially when exhausting every possibility) expends a lot of energy. Therefore, the default strategy is to use a heuristic. And the heuristic is chosen by pattern-matching the "feel" of the question. Unfortunately, the feel of the original question doesn't trigger a heuristic which takes into account the boolean nature of marital status. So rather than assign Anne a value of {married | unmarried}, we assign Anne a value of {null} and call it a day.
  - dllthomas 12y ago
    And of course it requires assuming "unmarried" is not distinct from "widowed" and "divorced", which may or may not hold up.
    - phkahler 12y ago
      >> And of course it requires assuming "unmarried" is not distinct from "widowed" and "divorced", which may or may not hold up. Not really. Many people consider those other options as special cases of "married" or "unmarried". In that case, how you match them up is not relevant to the problem because she still fits one or the other. She could also be a cat, which would change the answer.
      - dllthomas 12y ago
        I totally agree that '[m]any people consider those other options as special cases of "married" or "unmarried"'. It's possible it's most people. However, I assert that enough people consider "unmarried" different from "divorced" or "widowed" that the assumption your audience thinks the other way "may not hold up".

mbell 12y ago

I got it wrong, not due to lack of logic but due to lack of spending the time to untangle the strange wording. I read it as "Jack is looking at Anne, but Anne is looking at _Jack_." and assumed it was some sort of trick question. If they were really interested in testing logic they would deliver the problem in a clear manor rather than masking it strange wording.

lkrubner 12y ago

SPOILER ALERT (ANSWER OF RIDDLE BELOW): Like most people, my first thought was c. And yet, as I said, I suspect that if this had been presented as a bit of Java or Ruby, I would have been unlikely to make that mistake. I read English with a laziness that is different from how I read computer code.

deleted 12y ago
[deleted]

gjm11 12y ago

The failure mode isn't getting stuck, it's failing to notice that there's actual work to do. The way you get this one wrong is a thought process like this: "Well, obviously we only know about the first and third links in the chain, and we aren't told anything about the second one. So of course we can't tell whether there's a married person looking at an unmarried one because we have no information about any two directly 'connected' people." (But less explicit -- if you think about it in that much detail you're likely to think of brute-forcing the possibilities.) Or like this: "Well, let's see: A looks at B looks at C, A is married, C not. Does A->B have to be married->unmarried? No; B could be married. Does B->C have to be married->unmarried? No; B could be unmarried. So we're done." Once it occurs to you that you could just kind of brute force all the possibilities, you're going to get it right. The problem comes when you short-circuit the process. (And the reason why doing so isn't just stupid is that often this sort of "pruning" of mental effort is key to working things out efficiently. It just happens that in this case the prunability is illusory.)

Double_Cast 12y ago
To expand on this. At first glance, we don't know what value Anne has. But marital status is a boolean value. Since marital status is boolean, it follows by the Law of the Excluded Middle that Anne is either {married | unmarried}. If we brute force the question by simulating each possible value that Anne can assume (and follow the implications), we arrive at the correct answer. But imagine a case where we test for flavors of ice cream rather than marital status. > Jack is looking at Anne, but Anne is looking at George. Jack has chocolate ice cream, but George has vanilla ice cream. Is a person with chocolate ice cream looking at an person with vanilla ice cream? Can we correctly answer the new question? No, because Anne might have strawberry ice cream. A flavor isn't a boolean value! Also consider that simulation (especially when exhausting every possibility) expends a lot of energy. Therefore, the default strategy is to use a heuristic. And the heuristic is chosen by pattern-matching the "feel" of the question. Unfortunately, the feel of the original question doesn't trigger a heuristic which takes into account the boolean nature of marital status. So rather than assign Anne a value of {married | unmarried}, we assign Anne a value of {null} and call it a day.
- dllthomas 12y ago
  And of course it requires assuming "unmarried" is not distinct from "widowed" and "divorced", which may or may not hold up.
  - phkahler 12y ago
    >> And of course it requires assuming "unmarried" is not distinct from "widowed" and "divorced", which may or may not hold up. Not really. Many people consider those other options as special cases of "married" or "unmarried". In that case, how you match them up is not relevant to the problem because she still fits one or the other. She could also be a cat, which would change the answer.
    - dllthomas 12y ago
      I totally agree that '[m]any people consider those other options as special cases of "married" or "unmarried"'. It's possible it's most people. However, I assert that enough people consider "unmarried" different from "divorced" or "widowed" that the assumption your audience thinks the other way "may not hold up".