Handbook of the History of Logic: - Fordham University Faculty

452 Catarina Dutilh Novaes
than Ockham’s, and that on purely logical/semantic grounds — that is, it is not
motivated by ontological considerations (i.e. realism about universals) as it is in
the case of Wyclif and Paul of Venice (see chap. 2 of Paul’s treatise on supposition
in his Logica Magna — [Paul of Venice, 1971]). 20 Moreover, thanks to the position
he holds with respect to propositions in general, i.e. that they should not be
distinguished, he escapes the risk of introducing equivocation in mental language
even though he accepts different kinds of supposition in mental language.
However, the simplicity of Buridan’s doctrines, namely the exclusion of simple
supposition from spoken and written language and of all kinds of supposition
except for personal supposition from mental language, remained very appealing;
it is not by chance that the vast majority of nominalists sided with Buridan and
not with Albert, and that virtually all other upholders of simple supposition were
essentially motivated by ontological considerations.
2.1.2 A fourth mode of personal supposition?
As shown in T. Parson’s contribution to this volume, in the 14 th century the modes
of personal supposition were virtually always associated to relations of ascent and
descent between propositions and the corresponding singular propositions. The
descensii ad inferiora are ‘certain types of inferences in which the common terms
of which the mode of supposition is being characterized is replaced by singular
terms falling under it, appearing in either nominal or propositional conjunctions
or disjunctions.’ [Klima and Sandu, 1990, 177]. Singular terms are proper names
or, as most frequent in the case of descents, demonstrative pronouns (usually
accompanied by the appropriate common term). For example, in the case of
‘Every man is an animal’, if it is the supposition of the term ‘man’ that is at stake,
then the singular propositions in question would be of the form ‘This man is an
animal’, ‘That man is an animal’ etc. (pointing at each individual falling under
the term ‘man’, i.e. each man), and the question is then how the descent to these
singular propositions can be made, i.e. either nominally or propositionally, and
either conjunctively or disjunctively.
Let the basic form of categorical propositions be represented as “ΦA is ΦB”, 21
where A and B are terms and Φ stands for any syncategorematic expression (such
as ‘Every’, ‘Some’, ‘No’ etc.) or the absence thereof. The different kinds of propositional
descent can then be characterized as:
Propositional conjunctive descent for A ⇔ from ‘ΦA is ΦB’ one can
descent to ‘This A is ΦB and that A is ΦB and ...’
20Notice though that in his Logica Parva Paul of Venice only recognizes personal and material
supposition.
21In fact, most often than not there was no quantifying expression preceding the predicate.
However, in a few cases there was such an expression (such as in an example to be discussed
below, ‘Socrates differs from every man’), and therefore for the sake of generality I introduce a
place-holder for a quantifying expression also in front of the predicate. See also [Karger, 1993]
formoreofsuchexamples.