Talk:Falsifiability

Ever since I first read Popper's The Logic of Scientific Discovery more than fifty years ago I have wondered why he leaned so heavily on modus tollens from propositional logic, while his argument for the falsification paradigm could have relied on reductio ad absurdum if he had used basic predicate logic. Take his example of the "black swan" whose observation falsifies the "universal law" that all swans are white. In predicate notation the argument would be: Premise 1: ∀(s) W(s) (e.g., All swans are white) implies ¬∃(s)(¬W(s)). Premise 2: B(a) implies ∃(s)(¬W(s)) (e.g., Swan 'a' is not white and is a swan implies that there exists a non-white swan). Conclusion: Therefore (by way of RAA), ¬∀(s) W(s) (e.g., The statement "all swans are white" is false). This seems far more elegant to me. The reason cannot be that Popper was not familiar with predicate logic. Does anyone know the answer? Ereunetes (talk) 21:07, 29 August 2025 (UTC)

I propose you move the question in the reference desk, because this is a page to discuss the article. Quickly, propositional logic does not use quantifiers. Popper uses them. So he has not limited himself to propositional logic. All swans are white uses a quantifier. It is formalized by Vx S(x) => W(x) or by Vx W(x) depending of the universe used to interpret x, but Popper would not formalize such simple logic. Dominic Mayers (talk) 21:32, 29 August 2025 (UTC)

The section Falsification and Open Science added by the IP 143.210.250.119 is in principle clearly related to the subject. However, it would be much more interesting if the link was made by sources, which would most likely provide more details about the connection. Currently, it looks like a promotion of this other subject and, unless we find sources that make concrete links with Popper's philosophy, I am inclined to remove it. I don't, because if Open Science is a well known initiative (I apologize for my ignorance), the independent sources most likely exist. I will have a quick look at it. Dominic Mayers (talk) 20:33, 4 October 2025 (UTC)

I easily found:

• Open Science and Epistemic Diversity: Friends or Foes?, written by philosopher Sabina Leonelli
• She also wrote this book.
• Professor Frank Miedema wrote Open Science: the Very Idea.

Dominic Mayers (talk) 20:37, 4 October 2025 (UTC)

The article is big and full of very specific language, which makes it rather hard to understand for people without degrees in philosophy (yes, I'm exaggerating). Imo, it would be useful to add something like "in other words, there must be a way to prove that a theory or a claim is false, otherwise it cannot be seen as scientific" in the beginning of the article. Xpoback (talk) 11:35, 4 January 2026 (UTC)

The problem is that even if this sentence seems simple, it has little to do with falsifiability, and its meaning remains unclear. It could be translated as the idea that a theory must make predictions, but that's already mentioned in the introductory summary. Also, falsifiability is, according to Popper, a technical aspect of his philosophy : critical rationalism. Perhaps, what you are looking for is in this other article. Dominic Mayers (talk) 14:40, 4 January 2026 (UTC)

Furthermore, it's not certain that the article appears complex to the general public but not to academics. The problem is more likely related to the person's worldview than to their level of education. The world view that is needed to appreciate falsifiability and critical rationalism in general is the view that the mental and the intellect (which is formally represented by logical or formal structures) has no access to reality and we must distinguish between this practical reality and the mental (i.e. formal or logical) level. Even the best logicians and mathematicians might have a lot of difficulties with that world view. Dominic Mayers (talk) 16:50, 4 January 2026 (UTC)