Handbook of the History of Logic: - Fordham University Faculty

The Development of Supposition Theory in the Later 12 th through 14 th Centuries 275
by the rules from causes, and they do not correspond to any kind of global quantificational
import. They are non-parasitic terms that occur inside of complex
clauses, or inside of complex terms derived from relative clauses. We focus here
on terms that occur within relative clauses.
Can we extend our rules for the causes of modes of supposition? The rules do not
presently address non-main terms. They do, however, assign modes of supposition
to non-main terms which are main terms of their local clauses, relative to the local
clauses, and they classify the complex terms containing them, relative to the main
clause. One might hope that these pieces of information would combine to tell
us the mode of supposition of the non-main term in the whole proposition. For
example, we can indeed predict that if a complex term C which consists of a term
modified by a relative clause has determinate supposition in a proposition P, and
if a term E has determinate supposition within the clause that forms the relative
clause, then E has determinate supposition in P. For example, the complex term
‘horse which some donkey sees’ has determinate supposition in:
Some man sees a horse which some donkey sees
And ‘donkey’ has determinate supposition in:
some donkey sees
Therefore, ‘donkey’ has determinate supposition in the whole proposition. (It is
easy to check that one may descend to a disjunction, and ascend back from any
disjunct.)
This fact has more application than might be thought. For this result also
applies to constructions generated from relative clauses, constructions such as
adjectives or participles in attributive position. So we can tell instantly e.g. that
‘spotted’ and ‘running’ have the same modes as that of the complex term containing
them in:
Some spotted donkey is running
Some running donkey sees a horse
Anything to which our Fronting rule applies automatically falls into this category,
as ‘king’ in‘Some king’s donkey is running’.
An additional rule is this: if a complex term C which consists of a term modified
by a relative clause has merely confused supposition in a proposition P, and if
a term E has determinate supposition within the clause that forms the relative
clause, then E has merely confused supposition in P. For example, the complex
term ‘horse which some donkey sees’ has merely confused supposition in:
Every man sees a horse which some donkey sees
And ‘donkey’ has determinate supposition in:
some donkey sees