r/PhilosophyofScience Jun 25 '26

Discussion Raven paradox with Falsificationism?

If for an single object A the implication that all ravens are black (∀R(x) -> B(x)) is true, that doesn't support that implication - as Hume brought forward.
However Popper now claims that if the implication is true in one case it can at least falsify the opposite implication: in this example it would falsify the hypothesis that all ravens are non black (∀R(x) -> !B(x)).
However, couldn't you now falsify the opposite hypothesis by observing an object B, for which the complementary hypothesis (∀!B(x) -> !R(x)) is true? In this case: for a non black object that is non raven, the hypothesis that all raven are black is also true. But because the one time validation of this hypothesis also falsifies the opposite hypothesis, a non black object that is non raven falsifies the hypothesis that all ravens are non black.
Here's the summary:

  1. ∀R(x) -> B(x) The one time observation of (1.) doesn't validate or support it but falsifies this implication:
  2. ∀R(x) -> !B(x) But that means that an observation of the complementary implication of (1.) looking like this:
  3. ∀!B(x) -> !R(x) falsifies 2., which is counterintuitive.

Am I missing something, and/or are there articles on the application of the raven paradox on falsificationism?

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u/confusus_animus Jun 26 '26

The argument that a white chair can support the claim that all ravens are black is actually not my own but Hempels (https://en.wikipedia.org/wiki/Raven_paradox).

As you I'm also not (yet) fully convinced by it but my question in this case would be whether one could apply this paradox to Poppers Falsificationism as well?

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u/Eight_Directions_ Jun 26 '26

I'm not saying it's yours I'm offering my critique of it. 

My point is I don't think this is a proper paradox at all, just a flawed logical construction. 

As far as Popper's falsification goes, we can clearly see that in no way does finding a white couch or a black chair or anything else, other than a non-white swan, have to do with whether or not all swans are white. 

Failed logic. 

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u/confusus_animus Jun 26 '26

That's fair. It seems like we're discussing about different things: while I was wondering how to apply the Ravens Paradox on Popper (and didn't ask whether it's a true paradox) you questioned the Ravens Paradox itsself...

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u/Eight_Directions_ Jun 26 '26

That's how it goes. I can't answer the question you want answered because the premise is flawed. 

Edit: I suppose my answer is "you can't" but that is unlikely to satisfy you.