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Can the material conditional in classical logic (e.g. propositional logic or predicate logic like first-order logic) be used to reason about propositions that are not factual? E.g., using a subjunctive proposition as in (1a) and (2a):

(1a) If it snowed in July in Washington DC, I would be amazed. [first proposition subjunctive, second factual]

(2a) If it snowed in July in Washington DC, I would become Emperor of the World. [both propositions subjunctive]

or using a counterfactual proposition as in (1b) and (2b)?:

(1b) If we had lost WWII, it would be tragic. [fist proposition counterfactual, second factual]

(2b) If we had lost WWII, fascism would have been ruling over the world till this day. [both propositions counterfactual]

Or is plugging in any type of proposition other than factual ones for propositional symbols like 'p' in, say, propositional logic, conceptually wrong, probably yielding some anomalous results of sorts?

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