Which answer in this list is the correct answer to this question? (2017) - <AUTHOR> https://math.stackexchange.com/questions/2217248/which-answer-in-this-list-is-the-correct-answer-to-this-question <comment><USER2> Here is a single python statement that solves the problem:

        print([
            q for q in itertools.product((True, False), repeat=6)
            if q == (
                all(q[1:]),  # 1. All of the below.
                not any(q[2:]),  # 2. None of the below.
                all(q[:2]),  # 3. All of the above.
                any(q[:3]),  # 4. One of the above.
                not any(q[:4]),  # 5. None of the above.
                not any(q[:5]),  # 6. None of the above.
            )
        ])

[https://gist.github.com/lovasoa/f2b4ed93e755bf4172583d28f206...](https://gist.github.com/lovasoa/f2b4ed93e755bf4172583d28f20635a3)

<comment><USER3> A less clever solution, using the wonderful z3

      import z3
      answers = [z3.Bool(f"answer{i}") for i in range(1,7)]
      implications = [
          z3.And(answers[1:]),         # All of the below
          z3.Not(z3.Or(answers[2:])),  # None of the below
          z3.And(answers[:2]),         # All of the above
          z3.Or(answers[:3]),          # Any of the above
          z3.Not(z3.Or(answers[:4])),  # None of the above
          z3.Not(z3.Or(answers[:5]))]  # None of the above
      constraints = [z3.Implies(ans, impl) for ans,impl in zip(answers, implications)]
      z3.solve(constraints)

<comment><USER4> Not enough constraints. You must (EDIT: should? see discussion below) also constrain that there is exactly one `answer{i}` which is true, and all the implications should be equalities (else, for example, 6 is a valid answer, even though that would imply 5 is true and thus contradict 6).

It just so happens that the first result Z3 finds is the correct one. But if you exclude that result with an additional constraint, it will find another. (This is general is a good way to check your work.)

(I just did the same exact exercise with Z3 and CVC4, but using SMTLIBv2 syntax.)

<comment><USER5> I don't think there is any constraint that a single answer is true, otherwise the exercise wouldn't list "All of them" as a possibility.

<comment><USER4> I feel like it's implied by the question itself? "Which answer [singular] is the [definite article] correct answer"

But you may be right. I detest word puzzles for exactly this type of ambiguity.

Same goes for implication vs. equality. Why "should" 5 being true contradict 6 being correct? Just because 5 happens to be true doesn't necessarily mean it is "the" "correct" answer. The "real" answer depends on an interpretation of the English-language formulation that _most_ people will apply, but not all.

<comment><USER6> The puzzle itself contains enough contradictions that a single answer is forced. So it is unclear from the question, but the result is definite: There is exactly one answer. (Of course, that fact is not obvious.)

</comment></comment></comment></comment></comment></comment><comment><USER7> Similar one I enjoyed in the Naive Bayes article from yesterday [https://blog.floydhub.com/naive-bayes-for-machine- learning/](https://blog.floydhub.com/naive-bayes-for-machine-learning/)

      Multiple Choice: If you choose an answer to this question at random, what is the chance you will be correct?
      A) 25%
      B) 50%
      C) 60%
      D) 25%

<comment><USER8> What's the correct answer?

<comment><USER9> Undefined. It's a paradox.

</comment></comment></comment><comment><USER10> I've always thought of these as "Wayside School" problems, because I first encountered them in the children's book, Sideways Arithmetic From Wayside School by Louis Sachar. I highly recommend it for any child who is into puzzles. I really enjoyed how the book deconstructed the format of tests and quizzes that I was so familiar with at the time. My favorite section was the sideways math, where words are added or multiplied and you had to deduce the values of the letters. E.g.,

          D O G
        x   A D
        _______

          D O G
        A D O
        _______

        A G O G

Maybe children don't learn to do arithmetic like this anymore and this section will be utterly impenetrable to them.

<comment><USER11> Since we're off subject, and Homer Jones made the NFL's best something, I offer: FRAN + JONES = SCORE

</comment></comment><comment><USER2> This is the kind of things that are a real pleasure to model in Haskell. Here is a nice solution:

        solve funcs = filter (matches funcs) (possibilities funcs)
        matches funcs truths = truths == zipWith (($).($truths).flip) funcs [0..]

        possibilities [] = [[]]
        possibilities (x:xs) = concatMap (\x -> [True:x, False:x]) (possibilities xs)

        all_of = ((and.).)
        one_of = ((or.).)
        none_of = (((not.or).).)

        the_above = take
        the_below = drop.(+1)

        main = mapM_ putStrLn $
          zipWith
            (\i s -> "Answer number " ++ (show i) ++ " is " ++ (show s))
            [1..] $
            head $ solve [
              all_of  the_below,
              none_of the_below,
              all_of  the_above,
              one_of  the_above,
              none_of the_above,
              none_of the_above
            ]

<comment><USER2> Run it online at: [https://repl.it/repls/WeeSlightExams](https://repl.it/repls/WeeSlightExams)

</comment></comment><comment><USER12> It seems that 5 is a winner, as stated in the accepted answer.

That's a pity, first I thought the goal of the question was to create an instance of Yablo's Paradox. Yablo's paradox is important because you cannot just argue that the paradox arises from an obviously incorrect definition, as people sometimes do for classical semantic paradoxes.

<comment><USER13> It would be very boring if it was paradoxical.

It would just be a more complicated version of:

1\. Statement 2 is wrong.

2\. Statement 1 is wrong.

Edit: I just looked up Yablo's paradox. It only works because there are infinite statements. Since there is a finite number of statements here, it could not be an instance of Yablo's paradox. Only a circular paradox.

<comment><USER14> One interesting aspect of this concrete example is that even though the two statements seem contradictory at first sight, there are in fact two assignments of truth values to statements so that no contradiction arises.

For instance, using Scryer Prolog and its SAT solver to model the situation:

        ?- sat(S1 =:= (S2 =:= 0)),
           sat(S2 =:= (S1 =:= 0)).

As answer, we get a symbolic expression that compactly captures all concrete solutions:

        clpb:sat(S1=\=S2)

This means that as long as the truth value of S1 is different from that of S2, the puzzle is solved. This is intuitively admissible, because if one of the statements is false, then the other is true.

It would be different if for example Statement 1 said "Statement 1 is false", because then there is no satisfiable assignment at all:

        ?- sat(S1 =:= (S1 =:= 0)).
        false.

<comment><USER13> I actually meant to have one say false and one say true. I just made a mistake in writing it out.

</comment></comment></comment></comment><comment><USER15> I'm a bit confused. It seems that we're all looking for the answer that can hold "true". That's fine, however, does 5 answer _this question_? From my understanding, the question itself is impredicative[1].

"Which answer in this list is the _correct_ answer to _this question_?"

Being self-referential makes it difficult to decide what correct in that context means. Does the question even allow for a no-answer/inconclusive result?

1\. [https://en.wikipedia.org/wiki/Impredicativity](https://en.wikipedia.org/wiki/Impredicativity)

edit: Alright, just noticed that user "DanielV" already covered its impredicativity (assuming that's what they mean by impredictive*)

</comment><comment><USER16> For an extended version, see this:

SELF REFERENTIAL QUIZ [http://faculty.uml.edu/jpropp/srat-Q.txt](http://faculty.uml.edu/jpropp/srat-Q.txt)

Soltion(s): [https://faculty.uml.edu/jpropp/srat.html](https://faculty.uml.edu/jpropp/srat.html)

</comment><comment><USER17> With Z3 : [https://rise4fun.com/z3](https://rise4fun.com/z3)

        (declare-const a Bool)
        (declare-const b Bool)
        (declare-const c Bool)
        (declare-const d Bool)
        (declare-const e Bool)
        (declare-const f Bool)
        (define-fun conjecture () Bool
        (and
            (= a (and b c d e f))
            (= b (and (not b) (not c) (not d) (not e) (not f)))
            (= c (and a b))
            (= d (or a b c))
            (= e (and (not a) (not b) (not c) (not d)))
            (= f (and (not a) (not b) (not c) (not d) (not e)))
            (xor a b c d e f)
        )
        )
        (assert conjecture)
        (check-sat)
        (get-model)

result :

        sat
        (model
        (define-fun f () Bool
            false)
        (define-fun b () Bool
            false)
        (define-fun a () Bool
            false)
        (define-fun c () Bool
            false)
        (define-fun d () Bool
            false)
        (define-fun e () Bool
            true)
        )

Old code was with another tool : [http://logictools.org/](http://logictools.org/)

      (a-> (b & c & d & e & -f)) &
      (b -> (-b & -c & -d & -e & -f)) &
      (c -> (a & b)) &
      (d -> (a | b | c)) &
      (e -> (-a & -b & -c & -d)) &
      (f -> (-a & -b & -c & -d & -e)) &
      ( a + b + c + d + e + f)

then

      (a <-> (b & c & d & e & f)) &
      (b <-> (-b & -c & -d & -e & -f)) &
      (c <-> (a & b)) &
      (d <-> (a | b | c)) &
      (e <-> (-a & -b & -c & -d)) &
      (f <-> (-a & -b & -c & -d & -e)) &
      ( a + b + c + d + e + f)

where it would crash

<comment><USER4> Implication is not strong enough. That permits e.g. f to be true and e to be false.

Also I don't know the specifics of the language that tool uses, but typically variadic XOR simply constrains that an _odd_ number of its operands are true. (It so happens that there are no solutions to this problem with 3 or 5 true answers.)

<comment><USER17> I changed the solver as it would crash when I corrected my code, and redone it with z3 online.

</comment></comment></comment><comment><USER18> In the same vein, there's the classic infamous self-referential aptitude test. [http://faculty.uml.edu/jpropp/srat-Q.txt](http://faculty.uml.edu/jpropp/srat-Q.txt)

<comment><USER19> I'm a huge fan of this, if only I had some sort of class to give this test to.

</comment></comment><comment><USER20> An expert system answer (Prolog, CLIPS) would be cool to see here.

<comment><USER21> Using the clpb library [0]:

      solution([A1,A2,A3,A4,A5,A6]) :-
            sat(A1 =:= A2*A3*A4*A5*A6),
            sat(A2 =:= ~(A3+A4+A5+A6)),
            sat(A3 =:= A1*A2),
            sat(A4 =:= A1+A2+A3),
            sat(A5 =:= ~(A1+A2+A3+A4)),
            sat(A6 =:= ~(A1+A2+A3+A4+A5)).

[0] [https://www.metalevel.at/prolog/puzzles](https://www.metalevel.at/prolog/puzzles)

<comment><USER22> Alternatively using z3 [0]:

      (declare-const a1 Bool)
      (declare-const a2 Bool)
      (declare-const a3 Bool)
      (declare-const a4 Bool)
      (declare-const a5 Bool)
      (declare-const a6 Bool)

      (assert (= a1 (and a2 (and a3 (and a4 (and a5 a6))))))
      (assert (= a2 (not (or a3 (or a4 (or a5 a6))))))
      (assert (= a3 (and a1 a2)))
      (assert (= a4 (or a1 (or a2 a3))))
      (assert (= a5 (not (or a1 (or a2 (or a3 a4))))))
      (assert (= a6 (not (or a1 (or a2 (or a3 (or a4 a5)))))))
      (assert (or a1 (or a2 (or a3 (or a4 (or a5 a6))))))

      (check-sat)
      (get-model)
      (exit)

The model is satisfiable where only a5 is true, anyone can run it themselves and play with it [1].

Additionally forcing a5 to be false by adding the following to the list of assertions:

      (assert (not a5))

And the model becomes unsatisfiable.

Edit: Finally, to make sure there's not some possible solution where a5 is true as well as another assertion you could alternatively add this assertion:

      (assert (and a5 (or a1 (or a2 (or a3 (or a4 (or a6)))))))

And the model also becomes unsatisfiable. So 5 only seems to be the correct answer.

[0] [https://github.com/Z3Prover/z3](https://github.com/Z3Prover/z3)

[1] [https://rise4fun.com/Z3/1DMW](https://rise4fun.com/Z3/1DMW)

<comment><USER3> I posted a solution using the python z3 library, which might be easier to use for people used to python, here: [https://news.ycombinator.com/item?id=21545143](https://news.ycombinator.com/item?id=21545143)

<comment><USER3> That solution was not correct, see [https://news.ycombinator.com/item?id=21568151](https://news.ycombinator.com/item?id=21568151)

</comment></comment></comment></comment></comment><comment><USER23> I feel the question is unnecessarily convoluted. To really answer the question, you have to recursively refer to the question itself. So to parse the question, I'm calling a function recursively without a stop condition. They could have just asked, which statement below is true. And for all intents and purposes the answer would have been the same.

<comment><USER24> I too am of the opinion the question recurses indefinitely, which would mean it's unanswerable and perhaps not even a valid question technically speaking.

</comment></comment><comment><USER25> LinkedIn's skill tests are hilariously poor. They ask unanswerable questions, and mistype the answers. The more familiar you are with the subject matter, the more uncertain you become.

<comment><USER26> I noticed those randomly one day and did a few of them. I failed the one for the primary programming language I have worked in for the past decade and passed ones for two different languages I have hardly used and AWS, which I barely know anything about outside of EC2 and R53.

I felt like there was a big difference in the quality of the questions and answers for each quiz. For the AWS one, for example, the phrasing used for most of the questions and answers made the correct answer basically obvious without actually knowing it to be correct.

<comment><USER27> Same with UpWork. Tests on these sites are largely garbage.

</comment></comment></comment><comment><USER28> We can easily narrow down the correct answer to "none of the above", which leaves 5 or 6. But since 5 is above 6 and is a correct answer, 6 cannot be correct. So it must be 5.

</comment><comment><USER29> I could be wrong, but the question is ill-stated; should be something like 'which of the following statements are true', I think, or maybe 'what is the only true statement in the following list.' It's been awhile since logic classes though, maybe those are essentially the same as the original question, I can't quite figure out what I think is wrong with the original question, it just doesn't seem quite right to me.

Also, 4 is ill-stated -- "One of the above is true" \-- does that mean _exactly_ one of the above is true, or _at least_ one of the above is true. Although in that case I don't _think_ it matters because 1/2 are mutually exclusive and 2/3 are mutually exclusive, and the combination of those two means that 1/3 are mutually exclusive., so only exactly one of 1-3 can possibly be true anyway.

</comment><comment><USER30> 6 can not be true because if it where then 1,2,3,4 & 5 would be false, but that would make 5 true as well which is a contradiction, therefore 6 can only be false

1 Can not be true because we just determined 6 as false so 1 can only be false

3 can not be true because we just determined 1 as false so 3 can only be false

With 1 and 3 now proven false, 2 can only be true if 4 is false, but if 2 is true then 4 would be true as well. This is a contradiction so 2 can not be true.

With 1,2 and 3 now proven false, 4 is false.

5 is true since we just proved 1,2,3 and 4 to be false

<comment><USER31> Everyone in the comment thread seems to be focused on whether each proposition can be true. This is looking for your keys under the lamppost despite the fact that you dropped them in the dark. It's easy to determine whether a proposition can be true.

But the question doesn't ask about that. It just asks "which of these is the correct answer to this question?" There are no stated criteria for being the correct answer, and there is no reason to assume that the correct answer must be true or even capable of being true.

Consider this other question:

        Which of the following is the correct answer to this question?
          (A) This one.
          (B) This one.

<comment><USER32> That's arguing about semantics. It seems obvious from context that the intended interpretation of "the correct answer" is "the only true answer" — since "true" and "correct" are nearly synonymous, and the use of definite article singular implies that there exists exactly one answer.

<comment><USER33> To be fair, making the argument that something is obvious from context is also arguing about semantics. The other poster makes a defensible point (as do you!).

</comment></comment></comment></comment><comment> northern-lights I didn't see a logical explanation that explains why an option is correct or not, so here's one:

Q Which answer in this list is the correct answer to this question?

1\. All of the below. 2\. None of the below. 3\. All of the above. 4\. One of the above. 5\. None of the above. 6\. None of the above.

I'll assume "is the answer" to be "True" and "is not the answer" to be "False" in my explanations to make it more readable.

Lets say 1 is True. This implies - 2, 3, 4, 5, 6 are also True. Now, if 2 is True, then it means 3, 4, 5, 6 are False. This contradicts what 1 says. So, 1 cannot be True.

Lets say 2 is True. This implies - 3, 4, 5, 6 are False. If 3 is False, it means both 1 and 2 cannot be True. Since, we've assumed 2 to be True, 1 can indeed be False, so this is consistent. If 4 is False, then it means either less than one or more than one out of 1, 2, 3 are True. Zero out of 1, 2, 3 cannot be True since it contradicts our assumption of 2 being True. So either two or three out of 1, 2, 3 have to be True. Since, we've already established than 1 is False, that leaves 3 to be True along with our assumption of 2 being True. But 3 cannot be True since it contradicts 2. So 2 cannot be True.

Lets say 3 is True. This implies 1, 2 are True. We've already established that 1, 2 are False. Moreover, 2 being True will contradict 3 being True. So 3 cannot be True.

Lets say 4 is True. This implies that exactly one of 1, 2, 3 is True. We've already established that they are False. So 4 cannot be True.

Lets say 5 is True. We now know that 1, 2, 3, 4 are not True. So, this is consistent. We'll come back to this.

Lets say 6 is True. This implies that 5 is False. If 5 is False, it means all of the above 5 - 1, 2 , 3, 4 are True which we've found not to be True. So 6 cannot be True.

That leaves only 5 to be answer to the question.

<comment><USER34> > _If 5 is False, it means all of the above 5 - 1, 2 , 3, 4 are True_

That is incorrect. "Not All False" does not imply "All True."

<comment> northern-lights You're right, my bad. Negation of None of the Above is False is Some of the Above is True. I will modify my explanation.

</comment></comment></comment><comment><USER35> Solution in Scala, with JaCoP:

      import org.jacop.scala._

      object Main extends App with jacop {
        def forAll(l: Seq[BoolVar]) = l.foldLeft[BoolVar](true) { case (r, m) => r /\ m}
        def forAny(l: Seq[BoolVar]) = l.foldLeft[BoolVar](false) { case (r, m) => r \/ m}

        val v = List.tabulate(6)(i => new BoolVar(s"Answer ${i + 1}"))
        v(0) #= forAll(v.drop(1))
        v(1) #= ~forAny(v.drop(2))
        v(2) #= forAll(v.take(2))
        v(3) #= forAny(v.take(3))
        v(4) #= ~forAny(v.take(4))
        v(5) #= ~forAny(v.take(5))
        satisfy(search(v, input_order, indomain_min))
        print("Solution: " + v.filter(_.domain.contains(1)).map(_.id).mkString(" "))
      }

Results in:

      Solution: Answer 5

</comment><comment><USER36> Maybe I made a mistake, but I think this can be solved really simply just by taking each option in turn, assuming it is correct and looking for an inconsistency.

1 can't be right because it both affirms and contradicts 2.

2 can't be right because it both denies and fulfils 4 (even if 'one' means 'one and only one', because we already know that 1 is false, and looking ahead we can see that 3 is also false).

3 affirms 1, which we already know to be false.

4 affirms one of 1-3, which we have determined are all false.

5 is correct, as demonstrated by our finding that 1-4 are all false.

6 is false; we would know this even if we hadn't already worked out that 5 was true, because 6 implies that 1-4 are all false, which implies that 5 is true.

<comment><USER37> Exactly, I'm not sure why people are writing code to solve this. Just needs a systematic approach.

</comment></comment><comment><USER38> x is unknown, T=True, F=False, ttt = x or x or x, otherwise all connected with "and"

By definition:

      #1: xTTTTT
      #2: xxFFFF
      #3: TTxxxx
      #4: tttxxx
      #5: FFFFxx
      #6: FFFFFx

Begin evaluation from 6.

Let's assume 6 is T so we have xxxxxT. In that case 5 need to be F. But if 5 is F, then any from [1,2,3,4] need to be T. But if any from [1,2,3,4] is T then 6 cannot be T. Thus 6 cannot be T, so it is F if correct answer exists.

Now we have: xxxxxF

Next, we try to set 5 to T: xxxxTF. 1 cannot be T, 2 cannot be T, since their last elements are different (TT!=TF, FF!=TF), 3 cannot be T because it requires 1 and 2 be both T , 4 cannot be T because (1 or 2 or 3) are F.

So we have: FFFFTF

Thus only 5 is True.

</comment><comment><USER39> It seems all of the answers assume "You cannot assume there is only one correct answer." However in "...answer in this list is the correct answer..." to my mind the word "the" requires only one correct answer. If it was worded '...a correct answer...' or '...one of the correct answers...' ok sure, there can be more than one. But as it stands there can only be one correct answer so the "correct" answers so far, are based on a false premise.

<comment><USER40> Regardless of the interpretation it's not a false premise. The uniqueness of the answer is just an assumption that we don't need.

Suppose the question was instead: "What is the unique real number x for which x^3 = 8?" We can guess and verify that x = 2 is a solution. And if we're allowed to assume that this equation has a unique solution, then that's enough. But if we work a little harder, then we don't actually need that assumption: we can prove that x = 2 is the unique solution.

Similarly, in the original problem we could guess and verify that FFFFTF is a solution. And if we're allowed to assume that the solution is unique, then we're done. But again, if we work a little harder, then we don't need that assumption: we can prove that FFFFTF really is the only solution.

</comment></comment><comment><USER41> The question implies there is one correct answer.

Do you agree it can be rephrased as "Which answers in this list are the correct answers to this question?", so as to make it more difficult, while keeping the same answer?

<comment><USER42> It could be rephrased that way without changing the answer, but I don't think it would be any harder that way. You can still start with question 1 and continue downward to logically deduce the answer.

</comment></comment><comment><USER43> Formal methods to the rescue: [https://math.stackexchange.com/a/3437635/115703](https://math.stackexchange.com/a/3437635/115703)

</comment><comment><USER44> If you like this kind of puzzle, check out [http://faculty.uml.edu/jpropp/srat-Q.txt](http://faculty.uml.edu/jpropp/srat-Q.txt)

</comment><comment><USER45> I love that someone wrote a script to try and solve this problem.

</comment><comment><USER46> The question is phrased to mislead as this is a constraint satisfaction problem over the boolean space 2^6. There may be 0, 1, or many correct answers.

</comment><comment><USER47> It's interesting that the StackExchange community explained the answer better than the professor did in the original question.

</comment><comment><USER48> If you enjoy this kind of puzzle, look up the famous SRAT - self-referential aptitude test.

</comment><comment><USER49> So tricky! Number 5 is the only one that works though I think

</comment><comment><USER50> Very interesting, thanks for sharing.

</comment><comment><USER51> Only the 5th is true, Metamath: $( <MM> <PROOF_ASST> THEOREM=noneabove LOC_AFTER=?

h50::noneabove.1 |- ( ph <-> ( ( ps /\ ch /\ th ) /\ ( ta /\ et ) ) )

h51::noneabove.2 |- ( ps <-> ( -. ch /\ ( -. th /\ -. ta ) /\ -. et ) )

h52::noneabove.3 |- ( ch <-> ( ph /\ ps ) )

h53::noneabove.4 |- ( th <-> ( ph \/ ps \/ ch ) )

h54::noneabove.5 |- ( ta <-> ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th ) )

h55::noneabove.6 |- ( et <-> ( ( -. ph /\ -. ps /\ -. ch ) /\ ( -. th /\ -. ta ) ) )

56:50:simprbi |- ( ph -> ( ta /\ et ) ) 57:56:simprd |- ( ph -> et ) 58:51:simp3bi |- ( ps -> -. et ) 59:57,58:anim12i |- ( ( ph /\ ps ) -> ( et /\ -. et ) ) 60::pm3.24 |- -. ( et /\ -. et ) 61:60,59:mto |- -. ( ph /\ ps ) 62:61,52:mtbir |- -. ch 63:50:simplbi |- ( ph -> ( ps /\ ch /\ th ) ) 64:63:simp2d |- ( ph -> ch ) 65:62,64:mto |- -. ph 66::3ioran |- ( -. ( ph \/ ps \/ ch ) <-> ( -. ph /\ -. ps /\ -. ch ) ) 67:53:notbii |- ( -. th <-> -. ( ph \/ ps \/ ch ) ) 68:67,66:bitri |- ( -. th <-> ( -. ph /\ -. ps /\ -. ch ) ) 69:68:anbi1i |- ( ( -. th /\ -. th ) <-> ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th ) ) 70::pm4.24 |- ( -. th <-> ( -. th /\ -. th ) ) 71:69,70,54:3bitr4i |- ( -. th <-> ta ) 72::nbbn |- ( ( -. th <-> ta ) <-> -. ( th <-> ta ) ) 73:71,72:mpbi |- -. ( th <-> ta ) 74::df-xor |- ( ( th \/_ ta ) <-> -. ( th <-> ta ) ) 75:73,74:mpbir |- ( th \/_ ta ) 76::xoror |- ( ( th \/_ ta ) -> ( th \/ ta ) ) 77:75,76:ax-mp |- ( th \/ ta ) 78:55:simprbi |- ( et -> ( -. th /\ -. ta ) ) 79::pm4.56 |- ( ( -. th /\ -. ta ) <-> -. ( th \/ ta ) ) 80:78,79:sylib |- ( et -> -. ( th \/ ta ) ) 81:77,80:mt2 |- -. et 82:51:simp2bi |- ( ps -> ( -. th /\ -. ta ) ) 83::pm4.56 |- ( ( -. th /\ -. ta ) <-> -. ( th \/ ta ) ) 84:82,83:sylib |- ( ps -> -. ( th \/ ta ) ) 85:77,84:mt2 |- -. ps 86:65,85,62:3pm3.2ni |- -. ( ph \/ ps \/ ch ) 87:86,53:mtbir |- -. th 88:87,75:mtpxor |- ta 89:65,85,62:3pm3.2i |- ( -. ph /\ -. ps /\ -. ch ) 90:89,87:pm3.2i |- ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th )

qed:90,88,81:3pm3.2i |- ( ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th ) /\ ta /\ -. et )

$= ( w3a simprbi mto wn wa mtbir wb sylib mt2 3pm3.2i pm3.24 simprd simp2d simp3bi anim12i simplbi wo notbii 3ioran bitri anbi1i wxo w3o pm4.24 3bitr4i nbbn mpbi df-xor mpbir xoror ax-mp simp2bi pm4.56 3pm3.2ni pm3.2i mtpxor )

ANZBNZCNZKZDNZOZEFNZVLVMVIVJVKACC ABOZVPFVOOFUBAFBVOAEFABCDKZEFOZGLUCBVKVMENOZVOHUFUGMIPZABCDAVQVRG UHUDMZBDEUIZDEUNZWBWCDEQNZVMEQWDVMVMOVNVMEVMVLVMVMABCUOZNVLDWEJUJ ABCUKULUMVMUPUAUQDEURUSDEUTVAZDEVBVCZBVSWBNZBVKVSVOHVDDEVEZRSZVTT DWEABCWAWJVTVFJPZVGDEWKWFVHFWBWGFVSWHFVLVSUELWIRST $. $)

<comment><USER52> Is this readable with more linebreaks?

<comment><USER51> Not editable anymore but here you are (cf. [http://us.metamath.org/metamath/set.mm](http://us.metamath.org/metamath/set.mm) ) :

h50::noneabove.1 |- ( ph <-> ( ( ps /\ ch /\ th ) /\ ( ta /\ et ) ) )

h51::noneabove.2 |- ( ps <-> ( -. ch /\ ( -. th /\ -. ta ) /\ -. et ) )

h52::noneabove.3 |- ( ch <-> ( ph /\ ps ) )

h53::noneabove.4 |- ( th <-> ( ph \/ ps \/ ch ) )

h54::noneabove.5 |- ( ta <-> ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th ) )

h55::noneabove.6 |- ( et <-> ( ( -. ph /\ -. ps /\ -. ch ) /\ ( -. th /\ -. ta ) ) )

56:50:simprbi |- ( ph -> ( ta /\ et ) )

57:56:simprd |- ( ph -> et )

58:51:simp3bi |- ( ps -> -. et )

59:57,58:anim12i |- ( ( ph /\ ps ) -> ( et /\ -. et ) )

60::pm3.24 |- -. ( et /\ -. et )

61:60,59:mto |- -. ( ph /\ ps )

62:61,52:mtbir |- -. ch

63:50:simplbi |- ( ph -> ( ps /\ ch /\ th ) )

64:63:simp2d |- ( ph -> ch )

65:62,64:mto |- -. ph

66::3ioran |- ( -. ( ph \/ ps \/ ch ) <-> ( -. ph /\ -. ps /\ -. ch ) )

67:53:notbii |- ( -. th <-> -. ( ph \/ ps \/ ch ) )

68:67,66:bitri |- ( -. th <-> ( -. ph /\ -. ps /\ -. ch ) )

69:68:anbi1i |- ( ( -. th /\ -. th ) <-> ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th ) )

70::pm4.24 |- ( -. th <-> ( -. th /\ -. th ) )

71:69,70,54:3bitr4i |- ( -. th <-> ta )

72::nbbn |- ( ( -. th <-> ta ) <-> -. ( th <-> ta ) )

73:71,72:mpbi |- -. ( th <-> ta )

74::df-xor |- ( ( th \/_ ta ) <-> -. ( th <-> ta ) )

75:73,74:mpbir |- ( th \/_ ta )

76::xoror |- ( ( th \/_ ta ) -> ( th \/ ta ) )

77:75,76:ax-mp |- ( th \/ ta )

78:55:simprbi |- ( et -> ( -. th /\ -. ta ) )

79::pm4.56 |- ( ( -. th /\ -. ta ) <-> -. ( th \/ ta ) )

80:78,79:sylib |- ( et -> -. ( th \/ ta ) )

81:77,80:mt2 |- -. et

82:51:simp2bi |- ( ps -> ( -. th /\ -. ta ) )

83::pm4.56 |- ( ( -. th /\ -. ta ) <-> -. ( th \/ ta ) )

84:82,83:sylib |- ( ps -> -. ( th \/ ta ) )

85:77,84:mt2 |- -. ps

86:65,85,62:3pm3.2ni |- -. ( ph \/ ps \/ ch )

87:86,53:mtbir |- -. th

88:87,75:mtpxor |- ta

89:65,85,62:3pm3.2i |- ( -. ph /\ -. ps /\ -. ch )

90:89,87:pm3.2i |- ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th )

qed:90,88,81:3pm3.2i |- ( ( ( -. ph /\ -. ps /\ -. ch ) /\ -. th ) /\ ta /\ -. et )

</comment></comment></comment><comment><USER53> answer - [https://math.stackexchange.com/a/3437700/725808](https://math.stackexchange.com/a/3437700/725808)

The question displays a lack of understanding of language, especially the relation between a word and its meaning. More specifically, the relation between a noun and its pronoun.

Suppose Question 1 was:

> "What day is it today?"

And suppose Question 2 was:

> "Which answer in this list is the correct answer to this question? > Friday, > Saturday, Sunday"

If someone asks, _' What question is the pronoun "this" in Question 2 referring to?'_

Then you can reply - _' Question 1'_

And then they can proceed to answer Question 2 as _' Saturday'_

Suppose I just ask you out of the blue : _' what's his height?'_

You will immediately respond : _' who are you talking about?'_

A pronoun must come AFTER a noun has been established. If it comes before, the speaker must clarify the noun after.

In other words, you must be able to do a Ctrl-H Find & Replace in the original sentence, and change "this" to whatever it's referring to, and the new sentence should still make sense. That is the point of pronouns.

If I ask _' what is the weather in this city?'_

Does that question make sense without mentioning the city's name either before or after? It might make sense grammatically, but practically, it is not answerable.

If you now come back and say - Just replace the pronoun "this" with the text of the question, then it becomes :

"Which answer in this list is the correct answer to "Which answer in this list is the correct answer to this question" question?

Is the question answerable now ? Still NO. Because there is still one unresolved "this". Ad-infinitum.

So, to answer your question:

> 'which question ?'

The question, as is, is not answerable. Because it does not make sense until you resolve what 'this' refers to. Until then, it is just a bunch of words without a corresponding meaning. It's not a paradox or a contradiction. Barber's 'paradox', 'This sentence is false' etc. all are basically just a poor understanding of language/pronouns.

You might as well ask :

> 'Which answer in this list is the correct answer to oogabooga question?'

</comment><comment><USER54> what is the question?

5 and 6 are the only possible. But if 5 is true then 6 is false

None of the above can be true only with "more than one of the above (but different than all, none or one)", but then we would not be talking about _the_ correct answer. It is assumed than only an answer can be correct.

I suppose than 6 then.

Updated: you are right, 6 can't be true, is the 5

<comment><USER55> I got as far as your first sentence - "what is the question".

I can't work out what the question is asking, so I don't know how to work out what answers are correct/incorrect.</comment></comment>


Libreboot T400 laptop now FSF-certified to respect your freedom - <AUTHOR> https://www.fsf.org/news/libreboot-t400-laptop-now-fsf-certified-to-respect-your-freedom <comment><USER2> In principle, this is a good thing but in practice you are not getting much computer for your money.

I do a lot of work using an HP Stream 11 running Debian Linux and recently for fun I have been writing and developing Ruby code on a Raspberry Pi. Even as a long term financial supporter of the FSF, I have to question why not to just use a cheap but capable modern $200 laptop?

It is unfortunate that more mainstream manufacturers don't offer FSF-certified versions of their best selling laptops.

<comment><USER3> > _why not to just use a cheap but capable modern $200 laptop?_

The problem is that those newer machines generally require some proprietary binary blobs in the firmware to be loaded on boot that are loaded and that is considered unacceptable by this FSF certification program. It happens that the hardware for these particular laptops work without any requiring any non-free binary blobs to be loaded.

<comment><USER4> The FSF has no problem with non-free binary blobs on hardware, as long as they're burned into ROM[0]. The idea is that the firmware burned into ROM is not user serviceable - that it's never intended to be replaced and is intrinsically a part of the hardware. To have a completely different view when it comes to firmware that is loaded at initialization time seems a bit silly to me. This code is just as intrinsically a part of the function of the device, but instead of having to swap a board back to get a firmware update the firmware can be updated in the field.

[0] [https://www.fsf.org/campaigns/free- bios.html](https://www.fsf.org/campaigns/free-bios.html), specifically: 'The ethical issues of free software arise because users obtain programs and install them in computers; they don't really apply to hidden embedded computers, or the BIOS burned in a ROM, or the microcode inside a processor chip, or the firmware that is wired into a processor in an I/O device. In aspects that relate to their design, those things are software; but as regards copying and modification, they may as well be hardware. The BIOS in ROM was, indeed, not a problem.'

<comment><USER3> My understanding is they draw the line at updatability: if someone else is able to change the code, then _they can exercise unjust power over you_ (i.e. there's a power asymmetry between you and the vendor over who controls the device), whereas if it is just a fact of life that you cannot update a mask ROM, it is possible that there is no malicious intent from the vendor. It makes sense from the historical perspective, when it was cheaper to use a mask ROM than to incorporate flash memory, and you had to think hard about whether you have an incentive to push updates to the device. The economic incentive to the vendor consequently acted as a proxy metric to distinguish hardware from software.

Admittedly, the line is more blurry now: you can do _unethical_ things in mask ROMs (via crypto) to exert power over the user, a la trusted boot and DRM, and you can make things updatable by accident despite having no intentions to do so simply because flash is cheaper and more straightforward to install than mask ROMs.</comment></comment></comment></comment>


Ask HN: Completely lost interest in CS in college ,any way to get back? - <AUTHOR> I used to have this burning passion for computers in Junior high, i was the only kid in HS that knew more that a sophmore in college,ran bunch of servers at home,did it conusting. They depression hit me,dropped out of high school i was still coding.Freshman year of college rolls around I had all these hopes and dreams of making it as a dev,working on small-medium scale projects contributing to the linux kernel etc.
But the system in my country is kinda rigged and forces freshman year students to take up general sciences like math,physics,engineering drawing,chemistry. I was unable to code the first year due to this, i did do some C embedded stuff but that was way to lame. By the time i hit second year i had lost all of my passion the only thing i wanted to do was study whatever that was thrown in front of me and have sex.
I lost myself somewhere along the way,in my third semester of Comp sci engineering i simply studied all of the 4 computer subjects like data structures,basic programming which i already knew in Hs like a zombie would scored some marks and literally did nothing,got involved with multiple  other vices and kept ignoring what i liked since i never felt like it.
Only in my fourth semester did i realize what i had been missing but now the problem is i cant seem to understand what i used to easily and what came to me naturally,even though i worked on some exciting small projects i can't feel the passion i had before. I have been reading some OS books and i feel dumb as a nut,this stuff used to excite me before,i used to easily understand this.
i ended up getting a management intern at a tech firm since i thought i have reached the end of my programming career. Didn't really like it,and i do want to get back to development,that is what i want to do but i feel dumb,really dumb.
I was the only freshman in my univ to win a inter-college hackathon in my freshman year,i cant even seem to recognise that person anymore. <comment><USER2> Step one, learn how to use punctuation correctly:

This: "college ,any" \- incorrect, the correct usage is "collage, any".

This: "collage,ran" \- also incorrect, the correct usage is "collage, ran" (space _after_ the comma, comma _adjacent_ to the previous word).

This: "coding.Freshman" \- incorrect, the correct usage is "coding. Freshman" (you sometimes find two spaces after the period, that is also acceptable).

The rest of your post is riddled with errors of these kinds. That and spelling/grammar errors, all of which make you appear sloppy. And a sloppy language using programmer is often a poor programmer. So step one is to begin correcting these issues.

<comment><USER3> <<<<<<<<<<<<<<

"Step one, learn how to use punctuation correctly: This: "college ,any" \- incorrect, the correct usage is "collage, any".

This: "collage,ran" \- also incorrect, the correct usage is "collage, ran" (space after the comma, comma adjacent to the previous word).

This: "coding.Freshman" \- incorrect, the correct usage is "coding. Freshman" (you sometimes find two spaces after the period, that is also acceptable).

The rest of your post is riddled with errors of these kinds. That and spelling/grammar errors, all of which make you appear sloppy. And a sloppy language using programmer is often a poor programmer. So step one is to begin correcting these issues."

>>>>>>>>>>>>>>>>>

[http://www.dictionary.com/browse/collage](http://www.dictionary.com/browse/collage)

Don't be an asshole.

</comment></comment><comment><USER4> Based on your story, I would advise you to get a day job that pays you a liveable salary and isn't too stressful. And then on nights and weekends, focus on building something that is fun and useful.

Make it a goal to get tons of users. Once you have those users, you'll be qualified to get a job in tech, or attempt to turn it into a biz

</comment><comment><USER5> I'd think it could be helpful to flip this question on its head: find things that excite you, that you intrinsically find motivating. Put some energy into getting re-acquainted with that energy within you rather than trying to get excited about something you have lost interest in and learn to cultivate that energy and see where it takes you.

</comment><comment><USER6> It seems uni and the working world killed your faith. Ask yourself the purpose of that. Don't follow what people are saying just because of their position. I never buy something new without making myself an opinion on it.

</comment><comment><USER7> Do you smoke weed? What you describe sounds like you picked up this side habit.</comment>


Letters to the Editor: Misleading Mathematicians [pdf] - <AUTHOR> http://www.ams.org/notices/201506/rnoti-p613.pdf

<comment><USER2> The referenced article is available here: [http://www.ams.org/notices/201502/rnoti-p165.pdf](http://www.ams.org/notices/201502/rnoti-p165.pdf)

</comment><comment><USER3> The original blog entry which we modified into the letter to the AMS:

[http://ethanheilman.tumblr.com/post/108115952435/a-response-...](http://ethanheilman.tumblr.com/post/108115952435/a-response- to-wertheimers-encryption-and-the-nsa)

</comment><comment><USER4> I wish the authors had focused on the design of DUAL_EC_DRBG, since that's a more objective and compelling response. Mathematical features of the standard make very little sense without a backdoor, and the original article provided essentially no justification. Rather, it attempted a distraction by pointing to alternative configurations and standards.

The authors might also have focused on the NSA's consistent refusal to deny that it backdoored DUAL_EC_DRBG. It is difficult to see what intelligence harm could come from such an acknowledgement. After the Heartbleed issue went public, for example, the NSA quickly denied that it had previous knowledge.

Unfortunately, the authors focus on NSA skullduggery and misconduct, citing primarily to non-expert (and semi-sensationalist) reporting. That's not very surprising, since Bruce Schneier is an activist critic. (As is Green, I'm not familiar with Heilman.) I think it undermines their case, though.

<comment><USER3> >Mathematical features of the standard make very little sense without a backdoor, and the original article provided essentially no justification. Rather, it attempted a distraction by pointing to alternative configurations and standards.

I agree and would happily sign a letter which made this case. The argument for a DUAL_EC_DRBG backdoor is overwhelming.

>Unfortunately, the authors focus on NSA skullduggery and misconduct, citing primarily to non-expert (and semi-sensationalist) reporting.

My primary objection, I can't speak for the other signers, was Wertheimer's misleading claims that the NSA does have a history of such skullduggery when there is also very strong evidence to the contrary.

We cited:

1\. propublica.org, as a source for a direct quotes from NSA documents.

2\. reuters, who are the primary source for the claim that the NSA paid RSA 10 million to make DUAL_EC_DRNG the default.

3\. blog.cryptographyengineering.com, Matthew Green's writing on this subject. Matthew Green has published an academic research paper at a top venue on DUAL_EC_DRBG [0] and is a Cryptography Professor at Johns Hopkins.

4\. Mollin's An Introduction to Cryptography, a Cryptography textbook. Richard A. Mollin was a Cryptography expert [1].

5\. Johnson's "American Cryptology during the Cold War: Book III" a History of the NSA written by the NSA.

Three of the five are experts within their areas. Two are from well established news organisations.

[0]: [http://dualec.org/](http://dualec.org/)

[1]: [http://leydenscalgary.sharingmemories.ca/site/Richard- Mollin...](http://leydenscalgary.sharingmemories.ca/site/Richard-Mollin.html)

</comment></comment><comment><USER5> Received 9 February, published in the June/July issue; I wonder why such a long turnaround time for a short letter?

(The publication is more or less monthly, see at [http://www.ams.org/notices/201506/](http://www.ams.org/notices/201506/) ).

<comment><USER6> long? If you look at [http://www.ams.org/notices/201410/rnoti-p1268.pdf](http://www.ams.org/notices/201410/rnoti-p1268.pdf) (google "AMS notices backlogs" for other years), few journals beat that for papers, and many go way over that.

And yes, a short letter is different, but they might have a backlog of other letters to publish, may not want to limit the amount of letters per issue, and, for all I know, that June/July issue might have gone to print in May.

Even if the editors worked at infinite speed, in the end, this still is a paper journal with its limitation on number of pages, ratio of articles to reviews to letters, etc.</comment></comment>


The land that no country wants (2016) - <AUTHOR> https://www.theguardian.com/world/2016/mar/03/welcome-to-the-land-that-no-country-wants-bir-tawil <comment><USER3> > On Egyptian maps, Bir Tawil is shown as belonging to Sudan. On Sudanese > maps, it appears as part of Egypt. In practice, Bir Tawil is widely believed > to have the legal status of terra nullius – "nobody's land" – and there is > nothing else quite like it on the planet.

This is wrong and the article later corrects itself:

> Their ties to the area may be based on traditional rather than written > claims – but Bir Tawil is not any more a "no man's land" than the territory > once known as British East Africa, where terra nullius was repeatedly > invoked in the early 20th century by both chartered companies and the > British government that supported them to justify the appropriation of > territory from indigenous people.

The fascinating thing is that the idea that Bir Tawil is, or ever was, terra nullius comes from atriciously bad Wikipedia pages on the subject (in the past even the West Bank was listed as terra nullius!). It likley was those that lead Jeremiah Heaton to think he could claim it by planting a flag there. Because you cannot find any scholarly sources claiming that Bir Tawil is terra nullius. So what must have happened is that one or more Wikipedians, with no legal training, must have found terra nullius described in some source and then started to give terra nullius designations to pieces of land that they thought fit.

Along comes a lot of clueless journalists and repeats Wikipedia's erroneous claims. Wikipedians in turn find these articles and inserts them as references into the articles and the circle is complete.

And fwiw, the literal translation of terra nullius isn't "nobody's land" it's "empty land". Ownership of land is orthogonal to whether it is inhabited. Examples of terra nullius would be Antarctica or tiny remote islands that sometimes pops up in the Atlantic far from any country's coast. Bir Tawil does't fit the bill because it is inhabited. Which state has sovereignty is unclear but we do know it is either Egypt or Sudan. There is no room for a third party to make any claims.

<comment><USER4> I've often wondered if you could use the process described above to create an historical event that never happened.

Create the Wikipedia page(s), some journalists write about it, then add those articles as references. I wonder if people might even say they remember it happening.

<comment><USER5> If the model worked well, any source reputable enough to be cited enough in Wikipedia would fact check it and drop it. But I'm not sure that would work today, apart from the most reputable newspapers

</comment></comment></comment><comment><USER6> A few years ago Norwegians officials tried to give Finland a mountain as a gift to celebrate Finlands 100 years as a free nation. Norway's constitution states the kingdom of Norway is "indivisible and inalienable", so they had to give it up.

[https://www.independent.co.uk/arts- entertainment/films/news/...](https://www.independent.co.uk/arts- entertainment/films/news/norway-finland-mountain-gift-present-border-birthday- anniversary-bj-rn-geirr-harsson-k-fjord-a7541941.html)

<comment><USER7> Too bad. Otherwise they could have traded some equal sized land back, like Finland and Sweden did with Märket.

[https://en.wikipedia.org/wiki/M%C3%A4rket](https://en.wikipedia.org/wiki/M%C3%A4rket)

</comment></comment><comment><USER8> "Every reputable travel agent we approached turned us down point-blank, citing the prevalence of bandit attacks in the desert. Thankfully, we were able to locate a disreputable travel agent." For some reason this story reminds me of Mos Eisley...

</comment><comment><USER9> Belgium and it's northern neighbour swap land as the delta shifts. I believe last time the Netherlands donated some land.

There is an island on the France Spain or Spain Portugal border which takes turn about. Easier than fighting.

Enclaves are a thing. Maastricht and Liege have a couple nearby I believe. Too hard to tidy up. Partially alienated land is in some jurisdictions forbidden to be given up in law. The attempt to donate a mountain in skandi counties hit a constitutional barrier because the leaders are pledged to indivisible boundaries.

<comment><USER10> Norway trades a wee bit of land with Russia, too - a couple of banks in the Pasvik and Grense Jakobselv rivers are traded back and forth as the currents shift them from one side to the other of the centerline, the bilateral agreement governing this calls for the border to be reviewed every 25 years.

One amusing tidbit I remember is that even as the border is to follow the centerline of the rivers, no country is to gain or lose territory when the border is reviewed - so there's still some room for arbitration; the net size of both countries is to be unchanged.

One of the officials involved in the Norwegian delegation claimed that Norway was the only country ever to have been ceded part of Russian territory in modern times, though I expect this to be one for the newspapers - <USER2> other states with a river border with Russia have similar agreements.

<comment><USER11> China got half of Bolshoy Ussuriysky island and Tarabarov island on Amur river in 2004.

</comment></comment></comment><comment><USER12> I do think there's something to be said about trying new experiments for nation states with different operating models. There's obviously been mixed reactions and outcomes with places like Liberland and Seasteads (not to mention the micronations) but I'm hopeful that a small country like Estonia/Lithuania/Singapore/Rwanda that wants to be internationally competitive will innovate heavily in governance, economic models, etc.

</comment><comment><USER13> Haven't read the whole article yet, but if I can put one unnecessary and unimportant opinion from the whole thing out there, I don't really like the flag Jeremia Heaton chose for his new country. I mean, it isn't terrible. I have seen worse but common man, you had the rare chance to create a new flag and you went with something that kinda has a seal in the middle of it (fourth principle of flag design). I mean it isn't the worst seal on a flag out there but at the same time the crown will surely not be destinct from a couple of hundred meters away even.

</comment><comment><USER14> If the article is too long to read, watch this video instead: [https://www.youtube.com/watch?v=J5iJSXaVvao](https://www.youtube.com/watch?v=J5iJSXaVvao)

<comment><USER15> Still too long. Do you have a summary in a tweet somewhere?

<comment><USER16> Veni, vidi, verti, cessi :o)

</comment></comment></comment><comment><USER17> I blame Disney for an unrealistic princess fantasy.

</comment><comment><USER18> It's disputed territory, but one thing is clear: that guy does not belong there and has no legitimate claim to that place whatsoever.

</comment><comment><USER19> > an American dad claimed a tiny parcel of African land to make his daughter a > princess.

Can I just point out that this would be a fantastic plot for a movie or a novel? Could throw a lot of interesting themes into this

<comment><USER20> From the article:

> Jeremiah Heaton, beyond the "kingdom for a princess" schmaltz and the > forthcoming Disney adaptation (he has sold film rights to his story for an > undisclosed fee) [..]

I'm not sure if this was meant seriously though.

</comment></comment><comment><USER21> Tl;dr: there are two versions of land borders in that region, and the land which _is_ valuable. Bir Tawil is a flip side of this coin. If one country claims it, they auto-lose the other side.

<comment><USER22> This seems quite naive as geopolitics go. One imagines China or the US, for example, would have no qualms about claiming both. "We assert Egyptian sovereignty over Hala'ib based on the treaty of 1899, and Egyptian sovereignty over Bir Tawil based on the inalienable historic right of the Adabda people to live under Egyptian rule."

Maybe it works better if you can afford to build a settlement there, like in Palestine, or an airstrip like in the South China Sea.

</comment></comment><comment><USER23> > "Are white people still allowed to do this kind of stuff?" good question

<comment><USER24> Are Chinese people white 'cos if so then maybe? Xinjiang, Tibet, South China Sea.

<comment><USER23> they have had claims on all of those for a few centuries now, they didn't all of a sudden travel across oceans and continents to proclaim it theirs

<comment><USER24> It's OK to claim an adjacent territory, bring in settlers, oppress the natives, etc, just not OK to cross water to do so. is that your position? Hardly?

<comment><USER23> no i never said that. i merely observed that a question in the article is legitimate. not sure how i got dragged into addressing whataboutism in this subthread but ok

</comment></comment></comment></comment></comment><comment><USER25> do citizens of Bir Tawil have to pay taxes? Why hasnt google bought it? Can multinational corporations set up banks there and avoid taxes altogether?

</comment><comment><USER26> If there's water there then there is value. Be a great place to plant greenhouses, grow flowers and with an airstrip fly them into the heart of Europe.

But it would take quite a bit of capital and without formal recognition and a security force then it's a pipe dream. A pleasant one, but still a pipe dream.

<comment><USER27> Actually, there is no water. Nor soil. Nor vegetation which would depend on the other two.

<comment><USER28> Drill deep enough, and you might find water.

You might also be able to buy water from somewhere.

Solar farms don't need water either...

Lack of security force might not be an issue - being stateless means no taxes, so your business can probably afford to just hire it's own security against bandits. Get a reputation for shooting bandits on sight, and they won't come close.

I think the biggest risk is that if you actually manage to build a city there, both of your neighbours might decide to claim your land as theirs unless you have an army to threaten them with, or UN protection, both of which might be hard to get.

<comment><USER29> > Get a reputation for shooting bandits on sight, and they won't come close.

On what basis do you make that claim?

Probable reality will show they'll just come with more armed bandits than you have security forces, assuming the value warrants it.

</comment></comment></comment></comment><comment><USER30> This kind of thing is why I am looking forward to "No Man's Sky" VR release tomorrow.

No-one is likely to complain when I colonize a planet far off the beaten track where the highest form of life is a small feline creature with tentacles.

<comment><USER31> Are people actually still playing One Mans Lie? I'd assumed everyone charge backed it on day one....

<comment><USER24> The company has actually redeemed its reputation by continuosly releasing updates, afaik. Not fair to malign them like that.

<comment><USER31> If I bought a broken car then the dealership spent the next two years slowly fixing it to match the sales pitch initially sold I'd still be pissed off.

Why do people allow game publishers to get away with the crap...

<comment><USER32> I'm not really following your analogy. A video game isn't a car, a car is a means of transportation that depending on your situation, is a requirement in order to get goods and retain employment. A video game is a hobby for most people, it's like watching movies or television. I'd say it'd be more similar to how people reacted to Lost's final seasons rather than a broken car.

One can separate the launch of the game, where clearly there was a lot of confusion and misleading information, from the events since. They have issued free updates for years. They received death threats and other harassment as well. I'm not saying you have to like the game, but I'm just confused as to what they're getting with.</comment></comment></comment></comment></comment>


Eloquent JavaScript - An interactive online book about programming  - <AUTHOR> http://eloquentjavascript.net/ <comment><USER2> I personally found this very useful. Thanks Nickb!

<comment><AUTHOR> You're very welcome! :)

PS: Love the site as well. Great tutorial.</comment></comment>


Minecraft will stop using Amazon's cloud - <AUTHOR> https://www.cnbc.com/2020/07/20/microsoft-minecraft-mojang-abandon-aws-for-azure.html <comment><USER2> Of course Minecraft itself doesn't require any servers to run. This is about Realms, Mojang's server hosting service (you can still run your own).

Why did they stay with AWS for so long? A long-running contract?

Meta: Out of 11 paragraphs 2 (5 and 9) actually have content, while the introduction is quite misleading.</comment>


Ask HN: Can you help me with some career advice? - <AUTHOR> Here's my situation. I'm a young engineer(25) with 3 years of industry experience. From the very first few days in this company, my manager gave me 100% independence to do something interesting. 2 years ago the company decided to transition into a brand new building, and that event has just happened. So, 2 years ago, I got this amazing opportunity to work on the digital version of this building, to make it as smart as possible. I am the designer and the implementer of the core component of this project, pretty much an operating system for the building, implemented in Haskell. I gave my heart and soul into this project, because I don't think I'll get this kind of opportunity ever again. Besides this, they sponsored every single conference I wanted to go to, I've had time for about 3 per year. They bought every book I needed and allowed me to work from home whenever I wanted, or come to work whenever I wanted. In less than a month, the project is about to be live, and will do a lot of stuff to help the employees be more productive at work. So this is what kept me going, and I've been extremely happy in my work. However:
1. Even though the pay is about the industry average, I've had to turn down a lot of offers this year(even 2x to 2.5x salaries) because in my head, developing a smart building and developing a website is simply laughable to compare.
2. I'm pretty much the only one in this company(about 600 in this location alone) that has this kind of freedom. I'm lying, a few people have joined the project throughout the years to help me out.
3. There's no real ambition around me. Nobody wants to go beyond the accepted level of quality and deliver something amazing, a few details that would really delight the users. I really have to push to make these things happen. <comment><AUTHOR> Cont:

4\. I'm not stagnating whatsoever, but it's getting harder and harder to ignore these issues. It's getting harder and harder to just think about my wellbeing and my project, and simply ignore the bigger picture. That is, the company tries to keep their employees at a certain average level. Don't get too good though, as they won't be able to pay you for that. So really good people just leave.

So, what would you do in my situation. I can tell you that i'm going to stay for a little longer to make sure that the project is rock solid and stable. But I feel like the really good engineers are somewhere else and the temptation of a higher pay is getting stronger. I really want to continue to work on this project, but how do I convince the manager(whose only real management was to give me a hard deadline) that I've done the equivalent work of a few people, and the current benefits are not enough.

Thank you.

</comment><comment><USER2> I feel like you've already done the hard legwork. Just see the project through if that is only a few more months, make sure it is solid and successful. Then interview and have offers on hand. Ask for a match (if you enjoy your current environment). If the agree, congrats. If they say no, then go somewhere else and learn how to do something else. Not difficult decision.

</comment><comment><USER3> Just don't get into the comfort zone. Keep learning and you're good. One more thing you're not going to lean if you're the only developer in your team.</comment>


Show HN: The Fizz Buzz T-Shirt.  - <AUTHOR>

It all started about two years ago. I went to an interview for web developer position. The person interviewing me made me very nervous, because he was kind of creepy. His first official interview question came in the form of good old Fizz Buzz. To my horror, I couldn't complete the exercise! I was too nervous to even think about code. To make a long story short, I did not get the job.
Since that fateful day, I've been wanting to make a fizz buzz t-shirt to wear on interviews and hacker gatherings. This is my lean foray into finding out if this is something people wuld like to wear. I know I would, because it can be such a conversation starter between hackers.
Since this is my MVP, I'm just testing out if there is demand for it. Whatever the outcome I will definitely share all of the data with hacker news, because we love data.
If more than a $100 worth of tshirts is sold, I will donate 10% to whatever charity hacker news (as a community) chooses. Any charity.
Go and check it out. Remember, this is my first MVP. Its a cool shirt. Its less than $25. You will get all the data from the experiment. If enough people buy a charity of your choice will receive 10% of the net profits.
Link to store:
http://www.cafepress.com/fizzbuzztshirt
I will be reading feedback here, and through my email (check my profile).
Note:
This is an incredible leap of faith for me. I know people here are very supportive, but I don't want to come off as spammy. I'm just iterating through ideas here, no wish to spam or offend anyone.  <comment><USER2> I like the idea of a T-shirt with a FizzBuzz solution on it.

That said, the code on this shirt isn't actually a correct solution to FizzBuzz.

Even ignoring the extra lines of output ("##is divisible by X," with a missing space), on numbers like 15, this program prints "fizz" and then "buzz" and then "FizzBuzz" (instead of just "FizzBuzz.")

Unless there's some intentional irony I'm missing, I would suggest fixing the code.

<comment><AUTHOR> It is intentional. The t-shirt is meant to be funny.

</comment></comment><comment><USER3> if you send to Turkey,I want to it :D

<comment><AUTHOR> Thanks for showing interest in the Fizz Buzz t-shirt. The printer I'm using to handle t-shirt production ships worldwide. Here is the link to their shipping page: [http://www.cafepress.com/cp/info/help/index.aspx?page=shippi...](http://www.cafepress.com/cp/info/help/index.aspx?page=shipping.aspx)

Its about seven dollars for shipping to Turkey.

If anything, just email me. :)</comment></comment>


Cassandra 2.1: now over 50% faster - <AUTHOR> http://www.datastax.com/dev/blog/cassandra-2-1-now-over-50-faster

<comment><USER2> I am very interested in why these improvements somehow only affect the CQL interface and not the Thrift interface: they sound like things that would affect core parts of query execution, well below the interface used to describe the query.

<comment><USER3> The most important change for this post was the reduction of overhead for processing each message off the wire, through improved thread scheduling/communication. The changes do not affect CQL, so much as the 'native' protocol - CQL over thrift is no faster/slower.

<comment><USER2> Ok, thank you: saying it affects the native protocol networking layer (and would not affect CQL over Thrift) totally makes it click for me; the post made it sound like CQL itself was affected. Again, thanks!</comment></comment></comment>


Dropbox updates transparency report, publishes data request principles - <AUTHOR> https://blog.dropbox.com/2014/02/our-commitment-to-transparency/ <comment><USER2> I know that last time these were posted, many were unimpressed because of the NSA backdoor into unencrypted traffic between data centers. Still, it's interesting to see how much more detailed their report is than either Facebook or Google's. I hope this pushes the others to expand their previous (extremely vague) disclosures.

<comment><USER3> Anyone want to create a Privacy Service that keeps, collates & updates these reports as they change? It could be useful for the companies themselves so that they could update language to 'industry standards' and otherwise watch how their peers keep up with both the law and the public.

<comment><USER4> Sounds a lot like what [https://tosback.org/](https://tosback.org/) intends to accomplish, only slightly different targets.

</comment></comment></comment><comment><USER5> They say you have to report requests in bands of 250, but do they specify that the phase of the bands must be zero? What if everyone phase shifted their bands so the actual number of reports was the minimum number of the band they reported? i.e. if you receive 10 requests, then the bands you use are -240 to 9, 10 to 259, 260 to 510, etc.

<comment><USER6> I think it wouldnt be good for Dropbox to push it^^</comment></comment>


Can Silicon Valley boot camps get you a $120K job? - <AUTHOR> http://tech.fortune.cnn.com/2013/10/10/silicon-valley-boot-camps/

<comment><USER2> "These crash courses accomplish in 12 weeks (or less) what top computer science schools might teach in four years."

Yeah about that, no.

</comment><comment><USER3> Has anyone from HN actually taken any of these courses and could comment on them from personal experience?</comment>


Ask HN: Is it just me, or is quite a bit of the internet down (us-west) - <AUTHOR> fast.com nordstrom.com linuxquestions.org java.com
Are not resolving DNS for me. Is there something going on?
What does resolve is painfully slow. <comment><USER2> _DNS resolution errors a minute ago [19:00 UTC October 28, 2019] In-Progress:_

 _We have identified an issue that is currently causing DNS resolution errors while trying to access customer websites. The issue appears to have started around 18:35 UTC on October 28, 2019. We are actively working on the mitigation and will keep this advisory updated as we make progress. We apologize for the impact._

 _In the interest of time, we are providing you the most current information available, which may be subject to changes, corrections and updates._

<comment><USER3> link?

<comment><USER2> You have to log into their site.

</comment></comment></comment><comment><USER4> Looking at the new spikes on the graphs at DownDetector. Manual confirmation shows many are running Akamai DNS. Haven't gone through all of them yet.

[https://downdetector.com/](https://downdetector.com/)

</comment><comment><USER5> [https://weather.com](https://weather.com) is also not working for me

<comment><USER2> As an alternate, try weather.gov

[1] - [https://www.weather.gov/](https://www.weather.gov/)

</comment></comment><comment><USER6> Trello is down for me. A number of other sites seem unusually slow/down, too.

</comment><comment><USER3> Akamai's dns hosting?

</comment><comment><USER7> oreilly.com is down as well for all users globally. They're blaming the electricity company

<comment><USER3> fast/nord/etc are failing dns

</comment></comment><comment><USER8> Steam down

Trello unstable</comment>


Tony Hoare / Historically Bad Ideas: "Null References: The Billion Dollar Mistake" - <AUTHOR> http://lambda-the-ultimate.org/node/3186

<comment><USER2> This makes me wonder what really is the biggest mistake by a single individual in $ ?

<comment><AUTHOR> Once I read a book on compilers, can't recollect the name, that quoted Niklaus Wirth. Basically, he said that the hardest part in designing a language is to decide on what is to be left out. That idea and Hoare's reflection, seem to confirm the hypotheses that most woes in human endeavor seem to stem from gratuitous - often in hindsight, omission or commission to something.</comment></comment>