# Einstein's Intelligence Quiz ?

i have seen this riddle last year from a differnet forum:) really good quiz.. i wasn't able to solve it..but my cousin got it..and shockingly enough my dad too..

if you have good logic you can solve this riddle.. the 98% thing isn't really true .

JamesU
Gold Member
THis thread is three years old, and welcome to PF

Lol, I finished the puzzle in less than 10 mins, but I didn't see the question ("Who owns the fish?"). For about 5 minutes, I kept re-reading the page for mistakes or soemthing.

RageSk8 said:
Einstein himself did not have an amazingly high IQ (161 I believe).
That's amazingly high to me. :P

1314920 said:
the 98% thing isn't really true.
Actually, I expect the 98% thing is true. No one in this thread got the right answer. A second thread with the same puzzle appeared in Physics Forums about a year or so ago with the correct answer which I repeat below:

No one has a fish. The only time a fish is mentioned is in the question. That is the 'Einstein' angle. Einstein's special theory requires you to abandon the unjustifiable assumption of absolute space and time, just as this puzzle requires you to abandon the unjustifiable assumption that one of the pets is a fish.

You are correct that as a straightforward logic puzzle, this one is not particularly difficult. That, together with the "98% thing" is in itself a clue.

Actually it's a trick question. The text in the puzzle says that it is solvable. There are 4 pets mentioned in the clues. The 5th pet is not mentioned. Since the puzzle is solvable, there must be a fish as the 5th pet. If the 5th pet is something else, you cannot say who owns the fish, and the puzle is inherently not solvable.

turbo
Gold Member
Thanks to 1314920 for resurrecting this thread. I took about 7-8 min with a pen and a 3x5" piece of scrap paper. I made two tables. One diagramming the houses and one listing the associations. Using a left to right convention, I got the Norwegian in the first house with a blue house next to him, and the rest of the stuff just fell together.

daveb said:
The text in the puzzle says that it is solvable.
Yes. The solution is No one has a fish.

What a fun quiz! I got halfway by thinking rationally, and then the rest just started falling into place like guesswork.

daveb said:
Actually it's a trick question. The text in the puzzle says that it is solvable. There are 4 pets mentioned in the clues. The 5th pet is not mentioned. Since the puzzle is solvable, there must be a fish as the 5th pet. If the 5th pet is something else, you cannot say who owns the fish, and the puzle is inherently not solvable.
Sure it is! I actually skipped over the fish question and went straight to the clues. I ended up with a configuration that fit the clues but had one empty spot. Obviously, that empty spot is for the fish.

A fish named "empty."

jimmysnyder said:
Yes. The solution is No one has a fish.
But that's my point. You can't specifically say that no one has a fish since the clues do not mention that there is no fish. There either could be or couldn't be a fish - you can't determine which (sounds vaguely similar to a possibly dead cat in a box....) Since the puzzle says that it is solvable, the only logical conclusion is that there must be a fish present.

daveb said:
There either could be or couldn't be a fish - you can't determine which.
That's not so. If it were, then the problem would indeed be unsolvable. Therefore, there is no fish.
To sum up of the three possibilies:
1) Could be a fish or could be no fish: Wrong, ambiguous, violating the solvability clue
2) Is a fish: Wrong, too easy, violating the 98% clue.
3) Is no fish: Right, satisfies all clues.

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The best answer possible is to encompass the uncertainty:

"If any of the 5 people own fish, the German is the one that owns them."

However, if the problem is guaranteed solvable, which it states it is (at least in this particular quotation of the puzzle-- I expect that the original problem did NOT state this), then daveb is correct, the German necessarily has the fish.

However, if the problem ONLY stated that 98% could *NOT* solve the problem (which I expect Einstein directly stated), and did NOT state that the problem was definitely solvable, then the answer could be that nobody owns the fish, and that the problem is unsolvable, because the statement does not reference whether the remaining 2% could solve the problem.

And, because Einstein said it, and such a percentage is wildly stupid to even bother attempting to approximate, the liklihood is that the problem is NOT solveable, therefore meaning that there are two possible solutions, equally valid, either no fish, or a German-owned fish.

DaveE

jimmysnyder said:
That's not so. If it were, then the problem would indeed be unsolvable. Therefore, there is no fish.
To sum up of the three possibilies:
1) Could be a fish or could be no fish: Wrong, ambiguous, violating the solvability clue
2) Is a fish: Wrong, too easy, violating the 98% clue.
3) Is no fish: Right, satisfies all clues.
Sorry, that's rather flawed, thanks to 2). Stating "too easy" is an assumption on your part with no basis in logic, but instead on qualitative analysis which is uncertain. "Easy" is not a quantifiable factor.

Your assumption is likely based on the small group of people you have seen attempt to tackle the problem, which hardly constitutes a fair distribution of population. Further, there's other implications that may result that you're not considering, like:
- Language - Can someone who doesn't speak English solve the problem?
- Education - How has education changed in the world since Einstein's time?

If you're going to state that it's "too easy", that's fine, but that immediately invalidates the certainty of your claim, unless you can back that up with significant numbers. And even *then* it's still only "probable" unless you can actually test at least 100% of all humans on the planet. And even *then* it's invalid, unless you can test 100% of all humans on the planet as of when Einstein made the assumption.

DaveE

The problem doesn't say that you will like the solution, only that it has one. By the way, I seriously doubt that Einstein created the puzzle or even heard of it. Rather, I think his name is an extra clue about making unjustifiable assumptions. In my opinion, the puzzle is not the easy one that you can find in booklets at the checkout counter of your local supermarket and which a large percentage of people can solve. It is more subtle (and therefore more interesting) than that.

jimmysnyder said:
The problem doesn't say that you will like the solution, only that it has one.
Ok... so... you agree that the only distinct solution is that the German owns the fish then, and that by allowing the possibility of "no fish" makes for an unsolvable puzzle?

jimmysnyder said:
By the way, I seriously doubt that Einstein created the puzzle or even heard of it.
Yeah, that seems to be true. Googling for the answer appears to give lots of restatements of the puzzle, each stating that it's possibly attributed to Einstein, but nobody seems to give a reference. I'd imagine that Einstein's works are well documented enough so that somebody out there would have given a direct quote if it did in fact exist.

jimmysnyder said:
Rather, I think his name is an extra clue about making unjustifiable assumptions. In my opinion, the puzzle is not the easy one that you can find in booklets at the checkout counter of your local supermarket and which a large percentage of people can solve. It is more subtle (and therefore more interesting) than that.
Yes, I agree, which is why I think the answer is "If any one of the 5 specified people owns a fish, it is the German". It's a non-traditional answer that most people who could manage to untagle the logic wouldn't jump to, because they'll assume that the fish exists.

In truth, it's unstated. The existance of the fish is ambiguous, which actually *does* make the problem unsolvable if, by "solvable" you mean a being able to ascribe a individual to fish ownership unambiguously and verifiably, or verifiably proving that no individual owns a fish.

DaveE

Has it occurred to anyone that this problem may have not been in fact designed by Einstein and the 98% thing is... well... BS?

end3r7 said:
Has it occurred to anyone that this problem may have not been in fact designed by Einstein and the 98% thing is... well... BS?
Nooo! Really?

I am not satisfied after solving this puzzle. Perhaps I did it wrong. I paid attention to some parts but then I just started to kind of guess??. Like the house for the Swede, I just guessed that and I made some sence. I just tried something and it worked out. Am I the only one that feels this way?

I didn't have to "guess", everything worked out.

davee123 said:
"If any one of the 5 specified people owns a fish, it is the German".
I don't see how "If I only had one more clue I could impose my favorite solution on this thing." can be the answer. You don't have that one more clue.

jimmysnyder said:
I don't see how "If I only had one more clue I could impose my favorite solution on this thing." can be the answer. You don't have that one more clue.
In the quiz, there are only five animals, as given by the rules. If the quiz asks for fish, when four other animals are known, fish is the fifth animal, because the quiz only knows five animals. The quiz cannot ask for a sixth or a seventh.

jimmysnyder said:
I don't see how "If I only had one more clue I could impose my favorite solution on this thing." can be the answer. You don't have that one more clue.
Well, because it covers the flaw inherent in the problem, which is that the existance of a fish is implied, not explicitly defined. Your personal interpretation of whether or not a fish actually exists within the scope of the problem may be different than someone else's. That's why word problems can be phenomenally difficult to write.

Anyway, if you're unwilling to accept the conditional as an answer, then the answer must be that the problem is NOT solvable, OR that the German definitely owns the fish. In order to determin which is the case, you have to define "solvable" and establish whether "no fish" is a valid possibility, each of which are variable based on the reader, I would think.

DaveE

davee123 said:
it covers the flaw inherent in the problem
There is no flaw in the problem.

davee123 said:
the answer must be that the problem is NOT solvable, OR that the German definitely owns the fish.
The answer is No one owns a fish.

jimmysnyder said:
There is no flaw in the problem.

The answer is No one owns a fish.
Can you logically justify that answer? The only justification that I've seen you give is:

Hypothetical jimmysnyder said:
If the answer were "The German owns the fish", I believe, based on my personal experience, but not on any logical grounds, that many more than 2% of the population of humans on Earth would be able to solve the problem. Therefore, because 98% is a given and undisputable *fact* stated within the problem, the solution must be something more uncommon than "The German owns the fish".

Because we can prove logically that none of the other characters involved owns the fish as it would create a logical fallacy, the only remaining solution is that none of the characters involved owns a fish. Hence, because I *feel* that a solution in this case cannot reference any degree of ambiguity, the answer must be limited solely to nobody owning a fish.
But that reasoning isn't based on verifiable logic, it's based on experience.

DaveE

davee123 said:
The only justification that I've seen you give is: /QUOTE]
Perhaps you missed my post #30 in this thread.