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Handbook of the History of Logic: - Fordham University Faculty

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258 Terence Parsons<br />

The reverse principle also holds for determinate or merely confused supposition: 116<br />

From an inferior to a superior: If a (non-parasitic) term T has<br />

determinate or merely confused supposition in a proposition P , <strong>the</strong>n<br />

from P toge<strong>the</strong>r with a proposition stating that T ∗ is superior to T ,<br />

<strong>the</strong> proposition that results by replacing T by T ∗ in P follows.<br />

For example, ano<strong>the</strong>r <strong>of</strong> Aristotle’s first figure syllogisms follows by this principle:<br />

Darii<br />

Every M is P<br />

Some S is M<br />

∴ Some S is P<br />

Burley’s version <strong>of</strong> “from a superior to an inferior” is slightly more comprehensive<br />

than <strong>the</strong> version stated above: 117<br />

A consequence from a distributed superior to its inferior taken with<br />

distribution and without distribution holds good . . .<br />

I think that what he means by “and without distribution” is that if <strong>the</strong> quantifier<br />

sign preceding <strong>the</strong> distributed superior is changed so as to change <strong>the</strong> term<br />

from having distributive supposition to having determinate or merely confused<br />

supposition, <strong>the</strong>n <strong>the</strong> inference is still good. For example, not only is this a good<br />

consequence:<br />

Every A is B B is superior to A<br />

Every B is C B is distributed<br />

∴ Every A is C A replaces B in <strong>the</strong> second premise<br />

so is this:<br />

Every A is B B is superior to A<br />

Every B is C B is distributed<br />

∴ Some A is C A replaces B in <strong>the</strong> second premise, with ‘every’<br />

changed to ‘some’<br />

Ano<strong>the</strong>r example would be:<br />

116 Paul <strong>of</strong> Venice LP III.3 (171): from a lower-level term to its corresponding higher-level term<br />

affirmatively and without a sign <strong>of</strong> distribution and without any confounding signs impeding<br />

<strong>the</strong>re is a solid inference. E.g., ‘man runs; <strong>the</strong>refore, animal runs’.” [I don’t know why Paul<br />

does not require a “due mean” here, as he does for <strong>the</strong> inference from a higher-level term to its<br />

corresponding lower-level term.] Ockham SL III.3-6 (600) cites this rule: “ab inferiori ad superius<br />

sine distributione et affirmative est bona consequentia et simplex.” He <strong>the</strong>n gives a number <strong>of</strong><br />

counterexamples to it, such as examples in which terms do not have personal supposition. He<br />

<strong>the</strong>n qualifies <strong>the</strong> rule (page 601): “ab inferiori ad superius sine distributione et affirmative est<br />

bona consequentia si termini supponant personaliter et significative.” (cited in [Moody, 1965 p.<br />

288, note 1]). “From a superior to an inferior without distribution and affirmative is a good<br />

consequence if <strong>the</strong> terms supposit personally and significatively.”<br />

117 Burley Consequences in [Kretzmann & Stump, 1988 page 300].

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