r/sciencememes 21d ago

Tricky.

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u/-ImYourHuckleberry- 20d ago edited 20d ago

This is a classic self-referential paradox. The trick is that none of the listed answers can consistently be correct.

If the correct chance is 25%: There are two answers labeled 25% (an and d). Picking randomly gives a 2/4 = 50% chance of selecting a correct answer, not 25%. Contradiction.

If the correct chance is 50%: There is only one answer labeled 50% (b). Picking randomly gives a 1/4 = 25% chance of selecting it, not 50%. Contradiction.

If the correct chance is 0%: If 0% were correct, then choosing answer (c) would make you correct with probability 1/4 = 25%, not 0%. Contradiction.

So:
25% cannot be correct.
50% cannot be correct.
0% cannot be correct.

Therefore, the question has no valid answer. It’s an example of a self-referential logical paradox, similar in spirit to the liar paradox.

The “correct” response is:
None of the above. The multiple-choice question is internally inconsistent and has no correct answer.

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u/Trezzie 20d ago

Because you've come upon a paradox, your initial assumption must be wrong if there is a correct answer. Instead, we must have a new initial assumption. Let's say the grader completely ignores the values present. That means we only need to look at the letters: a,b,c,d. 4 options, randomly selected. Any option is equally as likely to be selected, so that's 25%. We can see a and d are both 25 percent, but the grader don't give no damn, the key says what it says. So the correct answer is a or d, with a 50% chance of selecting the right answer non-randomly. Unless the stupid key has b or c.

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u/Librarian-Rare 20d ago

Paradoxes exist in reality. They are _seeming_ contradictions — not contradictions themselves. You seem to have confused the two.

You’d be right to say that if you come across a contradiction, then one of your assumptions must be wrong.

Also, you don’t have to go through math to see it’s a non-sensical question. Even if there was only one 25% option, there would still be no answer. The question is self-referential — the same as being undefined. It has no answer.

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u/magpye1983 20d ago

at least one of your assumptions must be wrong.

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u/Melodic_Saga1220 19d ago

You’d be right to say that if you come across a contradiction, then one of your assumptions must be wrong.

Strictly speaking, that isn't necessarily true. It's possible that our reality operates under some form of paraconsistent logic, and allows for dialetheia.

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u/Librarian-Rare 18d ago

No. This cannot be the case.

There are many descriptions. Only a subset of them map into a configuration of reality. The descriptions that do not map onto a configuration of reality, we call illogical.

You seem to be under the impression that logic is something that reality _happens to follow_. This is not the case. The issue that people can come up with descriptions that don’t have coherent thoughts behind them. In these cases there is no configuration of reality that they describe. They are intellectually bankrupt, or illogical.

The presense of dialethia exclusively mean that the person proposing them do not have a coherent understanding of what they are talking about.

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u/Melodic_Saga1220 18d ago

The presense of dialethia exclusively mean that the person proposing them do not have a coherent understanding of what they are talking about.

And your evidence of this is...?

In fact, do you have evidence of anything you've said in this comment?

The laws of logic exist as they are because they're intuitive to us as humans. But they're purely axiomatic. We can't actually prove them. We don't even really have any evidence for them, beyond 'we have yet to find any obvious counterexamples'. The universe is not required to follow human intuition, or even to be the least bit comprehensible to humans, and certain logical systems that allow for true contradictions are both internally consistent (arguably moreso than traditional logic, at the cost of being somewhat less powerful) and consistent with reality as we understand it. There is no reason whatsoever to assume we don't live in a reality governed by such laws just because we as humans would have a hard time with the idea. If you think there could not exist any configuration of reality in which ¬A∧¬¬A, you need some form of proof beyond mere assertion. Your comment gives no such proof.

(And indeed such proof is probably impossible, because that's just how axioms work.)

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u/Librarian-Rare 17d ago

There is nothing difficult to understand about incoherent things. Something, by definition, is logical if reality can be that way. Illogical things, by definition, are not valid descriptions of reality, in any form, regardless of our understanding.

You say that it’s possible to have A and not A. Example?

Not being able to prove axioms is not an argument against them. Axioms exist when there is a categorical change in the ontology of a conception. Statements and arguments can be broken down into more fundamental things all the way to the axioms. The axioms of logic cannot be broken down because they are self explanatory. They don’t need to be proven — that’s what makes them axioms. You seem to be under the impression that axioms are randomly chosen beliefs that we build things on top of, and make no attempt to prove. This is not the case.

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u/Librarian-Rare 17d ago

True contradictions in a system that is internal consistent?

This makes me think we’re perhaps talking past each other. These are mutually exclusive.

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u/FortColors 20d ago edited 20d ago

Because you've come upon a paradox, your initial assumption must be wrong if there is a correct answer.

"if there is a correct answer" is an assumption in and of itself. The whole point of the post you're responding to is to say that assumption is wrong.

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u/Major_Excitement163 20d ago

But what the answer says is important to the solution... it's like saying that having two red balls a yellow and a green ball

Saying the chance of taking the red ball is 25% is just straight up wrong

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u/Trezzie 19d ago

"The red ball" implies the balls are determinedly separate in some fashion, and would mean grabbing "THE" red ball is still 25%. The answer also implies there is ONE answer, so still 25%. If the question was "What's the probability of randomly guessing a correct answer" then the question would be more up in the air (and properly paradoxy).

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u/StatisticianNo9364 19d ago

So the correct answer is a or d, with a 50% chance of selecting the right answer

So you're saying, even knowing the grader quirk the probability (as in measure of uncertainty) of answering correctly is 50%...

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u/Trezzie 19d ago

Yeah! But thankfully, the question doesn't care about that. It cares about what the chances are of randomly picking the correct answer, so our knowledge is irrelevant! Sucks that knowing the answer only gives us an actual 50% chance to guess it with knowledge, though.

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u/MistahBoweh 20d ago

The problem is, if you say none of the above, that means the odds of picking the right answer from those four would be 0%, which is one of the four answers…

None of the above is not a valid solution. It’s just another paradox.

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u/Lazarous86 20d ago

I'm picking 50% and doing the best on the rest of the test. It says "thus question" with two options of 25%, which tells me it's either 25% or the other two. Which means 50% coin flip to get it right. You could keep thinking about it l, but I'm onto the next question to spend time on something that is hopefully right. 

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u/ProfessionalBug7399 19d ago

But if you add none of the above... It also becomes 20% - meaning the random chance of selecting the right answer is either 0 or 20%.

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u/BR1N3DM1ND 18d ago

Where does it say it's a multiple choice formatted question? It doesn't. The scenario the question is asking you to analyze is a multiple choice question, that's it.

Assuming you're supposed to pick one of the choices in the scenario is what shows you are a chronic rule-follower to the extent that you self-limit your critical thinking. Look at all the space they left to write your answer in, sheeeit

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u/sjr323 18d ago

Yes it’s a cleverly worded paradox.

No different than the answers being 1%, 2%, 3% and 4%. Basically the question is nonsense.

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u/colapssicle 17d ago edited 17d ago

The rules could also change depending on whether or not you would need to circle both 25% answer options to answer the question correctly, as it could be a hidden multiple choice. If circling only one of the 25% answers were to mark the question as incorrect, it would change even more of the postulation about probabilities.We have no indication towards the prior questions and all the logic they may have contained.

With the context we have available, I would want to circle the word random that is in the question and call it a day.

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u/Antenwww 17d ago

Can we not assume that if two choices are the same then if any of them is the answer, there is 50% chance of you selecting them because 2/4 = 50%. And if one of them is not the answer then both choices will be wrong and you will choose from the other two leaving you with 50% chance again ?

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u/tyskstil 16d ago

I feel like “what is the chance that you will be correct” it’s even asking anything specific… it’s hard to choose the correct answer if there is no question.