For me Wason selection task has 2 logically valid solutions, identifyable by the 'logical system' in which the question is presented.
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Wason selection task
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Proposition: If a card has a vowel on one side, it will have an even number on the other.
Cards: [A] [B] [4] [7]
Problem: Which and how many cards need to be turned over to check whether the proposition holds true.
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The solution/s
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- Accepted solution: turn A (for proving true) and 7 (for proving false).
- My second solution: turn A (for proving true) and 4 (for proving true).
You could also turn all the cards. The problem here, I naively think, is that you are also turning cards that have no 'value' in proving the truth of the proposition, just because you can.
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My reasoning
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I think that the logic of the problem change based on what you want to achieve/prove.
ACCEPTED SOLUTION EXPLAINATION:
If I want to prove that the phrase is true, given that a false exist, than I could just turn A and 7:
- A --> To check if the proposition could be true by proving it true.
- 7 --> To check if the proposition could be true by proving it false.
MY ADDITIONAL SOLUTION EXPLAINATION:
If I want to prove that the phrase is true, without knowing anything else, than I could just turn A and 4 seeking for the truth:
- A --> To check if the proposition could be true by proving it true.
- 4 --> To check if the proposition could be true by proving it true again (to strengthen).
Why not B? Since knowing the other side, wouldn't give any additional information.
Why not 7? Since checking for the falsehood is not required, turning it wouldn't give any additional information.
While I understand the generally accepted solution, I'm not sure that mine is wrong, since the proposition asks to check the truth, and not necessarily the falsehood.
I will end up with the same conclusion even on the "beer/under 18" version.
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My mental context
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I'm not a phylosopher or a logician.
It is totally possible that I'm just confusing things or not understanding them well:
- Logic is not absolute, but it depends on a set of convention that allow us to agree on something.
- Logic is biased by a lot of things. A proposition could change its value based on the point of view from which it is evaluated.
- We should always verify our thoughts, against what "most people" accept as truth.
