Authors/Ockham/Summa Logicae/Book III-1/Chapter 53

Latin	English
Cap. 53. De mixtione ex propositionibus de necessario et aliis modalibus in tertia figura	Chapter 53. On the mixture of de necessario propositions and of other modals in the third figure.
In tertia flgura, si utraque sumatur in sensu compositionis, raro vel numquam valet mixtio, sicut non sequitur 'omnem Deum esse personam relativam est necessarium; omnem Deum esse immortalem est scitum a te; igitur aliquod immortale esse personam relativam est scitum a te’.	In the third figure, if both are taken in the sense of composition, the mixture is rarely or never valid, just as it does not follow that 'it is necessary that every God is a relative person; it is known by you that every God is immortal; therefore it is known by you that something immortal is a relative person'.
Si autem illa de necessario sumatur in sensu divisionis, non valet. Patet per eosdem terminos. Si autem utraque sumatur in sensu divisionis, si maior sit de necessario et minor de alio modo, semper sequitur conclusio de necessario si minor inferat suam de inesse. Et hoc, quia ex maiore de necessario in sensu divisionis et minore de inesse sequitur conclusio de necessario, et per consequens sequitur eadem conclusio ex antecedente ad illam de inesse et eadem maiore. Unde iste syllogismus est bonus 'omnis homo de necessitate est animal; omnis homo scitur esse albus; igitur aliquod album de necessitate est animal'. Si autem maior fuerit de alio modo et minor de necessario, sequitur conclusio de eodem modo de quo est maior, non de necessario, Unde sequitur 'omnis homo scitur esse albus; omnis homo de necessitate est creabilis; igitur aliquod creabile scitur esse album', sed non sequitur 'igitur aliquod creabile de necessitate est album’.	But if the proposition is taken de necessario in the sense of division, it is not valid. It is clear from the same terms. But if both are taken in the sense of division, if the major is de necessario and the minor of another mode, the conclusion de necessario always follows if the minor infers its assertoric. And this, because from the major de necessario in the sense of division and the minor assertoric, the conclusion de necessario follows, and consequently the same conclusion follows from the antecedent to that assertoric and the same major. Hence this syllogism is good 'every man is of necessity an animal; every man is known to be white; therefore something white is of necessity an animal'. But if the major is of another mode and the minor de necessario, the conclusion follows of the same mode as the major, not de necessario, Hence it follows 'every man is known to be white; every man is of necessity creatable; therefore something creatable is known to be white', but it does not follow 'therefore something creatable is of necessity white'.
Si autem illa de modo non inferat suam de inesse, mixtio non valet. ƿ	But if the modal proposition does not infer its assertoric, the mixture is not valid.