For any syllogism containing quantifiers such as "all," "some," and "no"/"none," you'll need predicate logic for the translation. Propositional logic alone won't suffice. But you could use propositional logic to translate a non-quantified argument that's at least similar to the syllogism: "If Hanna is a doctor, then she went to medical school. Hanna is a doctor. Therefore, Hanna went to medical school."
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Is it possible to translate a syllogism into propositional logic? This is the example: All doctors went to medical school. Hanna is a doctor. Hanna went to medical school. Thanks a lot, Sebastiano