Authors/Ockham/Summa Logicae/Book III-1/Chapter 43

Latin	English
Cap. 43. De mixtione talium modalium et propositionum de inesse in tertia figura	Chapter 43. On the mixture of such modes and assertoric propositions (of inherence) in the third figure.
In tertia figura, si illa de modo sumatur in sensu compositionis, non valet mixtio respectu conclusionis de modo consimili, addente aliquid super hunc modum 'verum', sumptum in sensu compositionis. Et ideo sciendum est primo quod numquam loquar postea de hoc modo 'verum', et hoc quia propositio de inesse et propositio de hoc modo 'verum' correspondens convertuntur, si propositio sit	In the third figure, if a modal proposition is taken in the sense of composition, the mixture is not valid with respect to the conclusion of a similar mode, if it adds something to the mode 'true', taken in the sense of composition. And therefore it must be known first that I will never speak later of this mode 'true', and this because the proposition of inherence and the proposition of this corresponding mode 'true' are convertible, if the proposition is
Sciendum est etiam quod mixtio ex illa de inesse et illa de modo in sensu compositionis non valet. Non enim sequitur 'omnem hominem esse animal est scitum a te; omnis homo est albus; igitur aliquod album esse animal est scitum a te', nam posito quod aliquod animal sit album et hoc nescias, praemissae sunt verae et conclusio falsa, sicut manifeste patet. Similiter non sequitur 'omnis homo est albus; omnem hominem esse animal est scitum a te; igitur aliquod animal esse album est scitum a te'. Patet per idem. Nec sequitur 'nullus homo est albus; omnem hominem esse animal est scitum a te; igitur aliquod animal non esse album est scitum a te'. Nec sequitur 'nullum hominem esse asinum est scitum a te; omnis homo est albus; igitur aliquod album non esse asinum est scitum a te'. Similiter non sequitur 'omnem hominem esse animal est per se; omnis homo est albus; igitur aliquod album esse animal est per se'.	It should also be known that the mixture of a premise of inherence and a premise of a mode is not valid in the sense of composition. For it does not follow that 'every man is known by you to be an animal; every man is white; therefore, that something white is an animal', for assuming that some animal is white and you do not know this, the premises are true and the conclusion false, as is clearly evident. Similarly it does not follow that 'every man is white; every man is known by you to be an animal; therefore that something white is known by you to be an animal'. This is clear from the same. Nor does it follow that 'no man is white; every man is known by you to be an animal; therefore that some animal is not white is known by you to be an animal'. Nor does it follow that 'no man is known by you to be a donkey; every man is white; therefore that something white is not a donkey is known by you'. Similarly it does not follow that 'every man is an animal per se; every man is white; therefore something white is an animal per se'.
Si autem illa de modo sumatur in sensu divisionis vel aequivalens ei, si maior sit de inesse et minor de modo, non valet mixtio. Non enim sequitur 'omnis homo est albus; omnis homo scitur esse animal; igitur aliquod animal scitur esse album'. Nec sequitur 'omnis homo est quantitas; omnis homo per se est animal; igitur aliquod animal per se est quantitas'. Nec sequitur 'nullus homo est albus; omnis homo scitur esse animal; igitur aliquod animal scitur non esse album', sicut non sequitur 'nullus homo est albus; omnis homo per se est animal; igitur aliquod ƿ animal per se non est album'. Tamen si modus sit negatus, bene sequitur, nisi sit modus negativus vel privativus formaliter vel aequivalenter, sicut est iste modus 'falsum'.	But if the modal proposition is taken in the sense of division or equivalent to it, if the major is of inherence and the minor is of a mode, the mixture is not valid. For it does not follow that 'every man is white; every man is known to be an animal; therefore, some animal is known to be white'. Nor does it follow that 'every man is quantity; every man is per se an animal; therefore, some animal is per se a quantity'. Nor does it follow that 'no man is white; every man is known to be an animal; therefore, some animal is known not to be white', just as it does not follow that 'no man is white; every man is per se an animal; therefore, some animal is per se not white'. However, if the modality is negated, it follows well, unless it is a negative or privative modality formally or equivalently, as is the modality 'false'.
Si autem maior fuerit de modo et minor de inesse, si maior fuerit universalis, semper est mixtio bona, quia semper per conversionem illius de inesse reducitur in primam figuram, ex qua et maiore erit syllogismus regulatus per dici de omni vel de nullo. Et ideo iste syllogismus est bonus 'omnis homo per se est animal; omnis homo est albus; igitur aliquod album per se est animal'. Et ideo tales syllogismi sunt boni 'omnis homo per se non est asinus; omnis homo est albus; igitur aliquod album per se non est asinus'; 'omnis homo scitur a te esse animal; aliquis homo est veniens; igitur aliquod veniens scitur a te esse animal'. Similiter iste 'Sortes scitur a te esse homo; Sortes est veniens; igitur veniens scitur a te esse homo'. Et iste 'omnis anima intellectiva scitur a Sorte esse substantia; omnis anima intellectiva est voluntas; igitur voluntas scitur a Sorte esse substantia'. Sed ista consequentia non valet 'voluntas scitur a Sorte esse substantia, igitur aliqua substantia scitur a Sorte esse voluntas'.	But if the major is of a mode and the minor of inherence, if the major is universal, it is always a good mixture, because it is always reduced to the first figure by the conversion of that of inherence, from which and the major there will be a syllogism regulated by 'to be said of all or none'. And therefore this syllogism is good: 'every man is an animal per se; every man is white; therefore some white thing is an animal per se'. And therefore such syllogisms are good 'every man is not a donkey per se; every man is white; therefore some white thing is not a donkey per se'; 'every man is known by you to be an animal; some man is coming; therefore some thing coming is known by you to be an animal'. Similarly this 'Socrates is known by you to be a man; Socrates is coming; therefore a coming thing is known by you to be a man'. And this 'every intellectual soul is known by Socrates to be a substance; every intellectual soul is will; therefore will is known by Socrates to be a substance'. But this consequence is not valid: 'will is known by Socrates to be a substance, therefore some substance is known by Socrates to be will'.
Similiter, si maior fuerit particularis, valet mixtio; sicut sequitur 'aliquis homo per se est animal; omnis homo est albus; igitur aliquod album per se est animal'. Et similiter sequitur 'aliquis homo per se non est asinus; omnis homo est animal; igitur aliquod animal per se non est asinus'. Et probatur talis syllogismus per syllogismum expositorium, de quo dictum est prius.	Similarly, if the major is particular, the mixture is valid; as it follows: 'some man is per se an animal; every man is white; therefore some white thing is per se an animal'. And similarly follows 'some man is not per se a donkey; every man is an animal; therefore some animal is not per se a donkey'. And such a syllogism is proven by the expository syllogism, of which we have spoken before.
Et ideo sciendum est quod in syllogismo expositorio semper, si maior sit de modo et minor de inesse, mixtio valet, sed si maior fuerit de inesse et minor de modo, non valet. Unde bene sequitur 'Sortes scitur esse animal; Sortes est albus; igitur aliquod album scitur esse animal'; sed non sequitur 'Sortes est albus; Sortes scitur esse animal; igitur aliquod animal scitur esse album'. Et ideo tales syllogismi non valent 'anima intellectiva est intellectus; anima intellectiva scitur a Sorte esse ƿ	And therefore, it should be known that in an expository syllogism, if the major is of a mode and the minor of inherence, the mixture is valid, but if the major is of inherence and the minor of a mode, it is not valid. Hence it follows well that 'Socrates is known to be an animal; Socrates is white; therefore, some white thing is known to be an animal'; but it does not follow that 'Socrates is white; Socrates is known to be an animal; therefore, some animal is known to be white'. And therefore, such syllogisms are not valid as 'the intellectual soul is the intellect; the intellectual soul is known by Socrates to be
forma substantialis; igitur aliqua forma substantialis scitur a Sorte esse intellectus'. Similiter non sequitur, secundum Philosophum, 'Deus est persona divina; deus scitur esse immortalis; igitur aliquod immortale scitur esse persona divina', sicut non sequitur 'hic Deus est immortalis; hic Deus creditur ab aliquibus esse corpus; igitur aliquod corpus creditur ab aliquibus esse immortale'. Tamen si maior in omnibus praedictis exemplis esset de modo et minor de inesse, esset mixtio bona.	a substantial form; therefore some substantial form is known by Socrates to be the intellect'. Similarly, it does not follow, according to the Philosopher, 'God is a divine person; God is known to be immortal; therefore some immortal thing is known to be a divine person', just as it does not follow 'this God is immortal; this God is believed by some to be a body; therefore some body is believed by some to be immortal'. However, if in all the above examples the major were of a mode and the minor of inherence, the mixture would be good.
Et tota ista diversitas et multa alia oriuntur ex hoc, quod dictum est prius, quod praedicatum appellat suam formam, non subiectum. Hoc est, quia ad veritatem propositionis de modo in sensu divisionis requiritur quod propositioni, in qua ipsum praedicatum, vel aliud omnino idem cum eo significans, praedicatur de pronomine demonstrante illud pro quo subiectum supponit, conveniat ille modus expressus. Non autem requiritur quod propositioni, in qua subicitur ipsum subiectum, vel aliud omnino idem cum eo significans, respectu praedicati vel respectu pronominis demonstrantis illud pro quo praedicatum supponit, conveniat talis modus per praedicationem. Sicut ad hoc quod haec sit vera 'album scitur esse musicum' requiritur quod aliqua talis sit scita 'hoc est musicum', 'illud est musicum', demonstrando aliquid pro quo subiectum suppomt, scilicet album. Sed ad hoc quod haec sit vera 'album scitur esse homo' non requiritur quod aliqua talis sit scita 'album est hoc' vel 'album est illud', quicumque homo demonstretur; nec requiritur quod aliqua propositio sit scita in qua album subicitur.	And all this diversity and many others arise from what was said before, that the predicate calls its form, not the subject. This is because for the truth of a modal proposition in the sense of division it is required that the proposition in which the predicate itself, or something else signifying the same as it, is predicated of a pronoun demonstrating that for which the subject supposits, that mode expressed befits that. But it is not required that a proposition in which the subject itself, or something else signifying the same as it, is subjected, with respect to the predicate or with respect to the pronoun demonstrating that for which the predicate supposits, that such mode befits that by predication. Just as for the statement to be true 'a white thing is known to be a musician' it is required that something such as 'this is musical', 'that is musical' be known, demonstrating something for which the subject supposits, namely white. But for the statement to be true 'a white thing is known to be a man' it is not required that something such as 'a white thing is this' or 'a white thing is that' be known, whichever man is demonstrated; nor is it required that any proposition be known in which the list is submitted.
Breviter igitur, haec est differentia inter terminum quando ponitur a parte subiecti et quando a parte praedicati quod si sit propositio de modo quod ad veritatem talis propositionis requiritur quod alicui propositioni in qua ipsummet praedicatum praedicatur, vel aliquid aliud omnino idem cum eo significant, - quod dico propter aliquas cavillationes quae possunt fieri contra aliqua dicta mea prius-, ƿ conveniat talis modus; sed non requiritur quod talis modus conveniat cuicumque propositioni in qua ipsummet subiectum, vel aliquid omnino idem cum eo significans, subicitur. Et ex isto oriuntur multa dicta et dicenda. Et est summe advertendum et memoriter retinendum ad sciendum quae propositiones de modo sunt verae et quae falsae, et quomodo convertuntur et quomodo non, et quomodo ex eis syllogizatur et quomodo non, et etiam ad sciendum quae propositiones de praeterito et de futuro sunt verae et quae falsae, et ad sciendum conversiones et modum syllogizandi ex eis, de quibus dictum est prius.	Briefly, then, this is the difference between a term when it is placed on the part of the subject and when on the part of the predicate, that if there is a proposition of a mode which for the truth of such a proposition requires that to some proposition in which the predicate itself is predicated, or something else signifying the same as it, - which I say because of some quibbles that may be made against some of my previous statements-, such a mode is appropriate; but it is not required that such a mode be appropriate to any proposition in which the subject itself, or something signifying the same as it, is subject. And from this arise many things that have been said and are to be said. And it is to be most attended and to be retained by memory to know which propositions of mode are true and which are false, and how they are converted and how they are not, and how one syllogizes from them and how one does not, and also to know which propositions of the past and the future are true and which are false, and to know the conversions and the method of syllogizing from them, of which we have spoken before.