The recovery of Aristotle’s logic during the twelfth century was a great stimulus to medieval thinkers. Among their own theories developed to explain Aristotle’s theories of valid and invalid reasoning was a theory of consequence, of what arguments were valid, and why. By the fourteenth century, two main lines of thought had developed, one at Oxford, the other at Paris. Both schools distinguished formal from material consequence, but in very different ways. In Buridan and his followers in Paris, formal consequence (...) was that preserved under uniform substitution. In Oxford, in contrast, formal consequence included analytic consequences such as ‘If it’s a man, then it’s an animal’. Aristotle’s notion of syllogistic consequence was subsumed under the treatment of formal consequence. Buridan developed a general theory embracing the assertoric syllogism, the modal syllogism and syllogisms with oblique terms. The result was a thoroughly systematic and extensive treatment of logical theory and logical consequence which repays investigation. (shrink)

Por que construir uma proposição com coisas? As razões de Gualter Burleigh em 1301.

Walter Burley claims throughout his career that the mind can make a statement out of things. Since things include entities that exist outside of the mind, Burley appears to be claiming that the mind can form a statement out of things that exist outside of it. Most scholars of Burley offer a deflationary reading of this claim, arguing that it confuses two distinct but closely related philosophical issues: the nature of propositional content, on the one hand, and the role of (...) facts in a compelling account of truth, on the other. But I argue that Burley means exactly what he says: that the mind can, quite literally, form statements out of things that exist outside of it. In Burley’s account, statements of this sort function as the propositional contents of our thoughts and written or uttered sentences. This account of propositional content is motivated by three more fundamental theses to which Burley is committed: referentialism, compositionality, and a claim about truth-conditionality I call intellectualism. (shrink)

O artigo aborda o tratado lógico de Geraldo Odon "De duobos communissimis principiis scientiarum" focando na noção de ens tertio adiacens: o ente significado pela totalidade da proposição e seu verificador. Odon o identifica ao sujeito dos princípios de não-contradição e terceiro excluído. O ens tertio adiacens também corresponde ao primeiro objeto adequado do intelecto e ao sujeito da lógica, a qual é entendida como a primeira ciência. Na segunda parte do artigo, localizamos Odon no debate historiográfico do realismo proposicional, (...) ao lado de Walter Burley. This paper deals with Geraldus Odonis' logical treatise "De duobus communissimis principiis scientiarum" by focusing on the concept of 'ens tertio adiacens': the being signified by the totality of the proposition and its truthmaker; Odonis identifies it to the subject of the principles of noncontradiction and excluded middle. The ens tertio adiacens also corresponds to the first adequate object of the intellect and to the subject of logic, which is understood as the first science. In the second part of the paper, we place Odonis in the historiographical debate of propositional realism, alongside Walter Burley. (shrink)