Authors/Ockham/Summa Logicae/Book III-1/Chapter 12

Latin	English
Cap. 12. De syllogismo ex obliquis in secunda figura	Chapter 12. On the syllogism from oblique cases in the second figure.
Ex istis, et dictis prius, potest patere quando syllogismus ex obliquis valet in secunda figura. Primo, quia si utraque praemissarum sit de obliquo a parte subiecti, sequitur conclusio de recto, sic ‘nullum equum videt asinus; omnem hominem videt asinus; igitur nullus homo est equus’. Similiter sequitur ‘cuiuslibet hominis est asinus; nullius rudibilis est asinus; igitur nullum rudibile est homo’.	From these, and what was said before, it can be seen when the syllogism from oblique cases is valid in the second figure. First, because if both premises are of the oblique on the part of the subject, the conclusion follows directly, thus: ‘a donkey sees no horse; a donkey sees every man; therefore no man is a horse’. Similarly, it follows ‘a donkey is any man's; a donkey is of no one who is rude; therefore no one who is rude is a man’.
Similiter, si utraque praemissarum habeat praedicatum obliquum, sequitur conclusio de recto, sic ‘nullus asinus est hominis; omnis bos est hominis; igitur nullus bos est asinus’.	Similarly, if both premises have an oblique predicate, the conclusion follows directly, thus ‘no donkey is a man’s; every ox is a man’s; therefore no ox is a donkey’.
Similiter, si maior affirmativa sit in recto et minor habens subiectum obliquum, sequitur conclusio habens subiectum obliquum, sic ‘omnis asinus est animal; nullius hominis est animal; igitur nullius hominis est asinus'.	Similarly, if the affirmative major is in the direct (nominative case) and the minor has an oblique subject, a conclusion follows having an oblique subject, thus 'every donkey is an animal; no man's is an animal; therefore no man's is a donkey'.
Similiter, si maior sit de recto et minor negativa, habens praedicatum obliquum, sequitur conclusio habens praedicatum obliquum, sic ‘omnis homo est animal; nullus asinus est animalis; igitur nullus asinus est hominis’.	Similarly, if the major is direct and the minor is negative, having an oblique predicate, a conclusion follows having an oblique predicate, thus ‘every man is an animal; no donkey is an animal's; therefore no donkey is a man's’.
Similiter, si maior sit negativa, habens subiectum obliquum, et minor de recto, sequitur conclusio habens praedicatum obliquum, sic ‘nullum hominem videt asinus; omne rudibile est asinus; igitur nullum rudibile videt hominem’.	Similarly, if the major is negative, having an oblique subject, and the minor is direct (nominative case), a conclusion follows having an oblique predicate, thus ‘a donkey sees no man; every rude thing is a donkey; therefore no rude thing sees a man’.
Similiter, si maior sit negativa, habens praedicatum obliquum. Et ƿ minor de recto, sequitur conclusio habens subiectum obliquum. Unde bene sequitur 'nullus homo videt asinum; omne rudibile est asinus; igitur nullum rudibile videt homo'. In aliis casibus non sequitur conclusio.	Similarly, if the major is negative, having an oblique predicate. And the minor is direct, the conclusion follows having an oblique subject. Whence it follows well that 'no man sees a donkey; every rude thing is a donkey; therefore no man sees a rude thing'. In other cases the conclusion does not follow.
Praedicta patere possunt convertendo propositiones et reducendo in primam figuram vel arguendo ex opposito.	The above can be made clear by converting the propositions and reducing them to the first figure or by arguing from the opposite.