Handbook of the History of Logic: - Fordham University Faculty

The Development of Supposition Theory in the Later 12 th through 14 th Centuries 159
medieval logicians accepted as the basis of their work.
I begin with an account of the forms of propositions that constitute the subject
matter of Aristotle’s symbolic logic. In keeping with medieval terminology, I use
the term ‘proposition’ to refer to what we today would call a meaningful sentence.
It stands for a sentence, not for an abstract meaning expressed by a sentence which
is named by a that-clause. So ‘Snow is white’ and ‘Schnee ist weiss’ are different
propositions. 3
1.1 Categorical Propositions
The simplest form of a proposition is a categorical proposition. In fundamental
cases this consists of two nouns (the “subject” and the “predicate”) separated
by the copula (is), with perhaps some other signs (often quantifier words) which
“modify” the nouns. Examples are:
Socrates — is — [an] animal.
Every animal — is — [a] donkey.
Some animal — is — [a] donkey.
in which the subjects and predicates are ‘Socrates’, ‘animal’ and ‘donkey’. The
words ‘every’ and ‘some’ modify the subject and predicate terms, but they are
not parts of the subject or predicate. The indefinite article ‘a/an’ is enclosed in
brackets since both Latin and Greek lack indefinite articles; in the original texts
there is nothing before the noun. The words ‘Socrates’, ‘animal’ and ‘donkey’ are
“categorematic”; these are the words that stand for individual things, ‘Socrates’
for the man Socrates, ‘animal’ for each and every animal, and ‘donkey’ foreach
and every donkey. The other words — the quantifier signs and the copula — are
called “syncategorematic” (meaning “with-categorematic”), since they occur with
(and affect) the categorematic terms.
The examples given above are affirmative. If a ‘not’ (which modifies the copula)
ora‘no’ is added, one gets a negative categorical proposition:
Socrates — is not — [an] animal.
No animal — is — [a] donkey.
Some animal — is not — [a] donkey.
‘Not’ and ‘no’ are syncategorematic signs.
Peter of Spain lays out the kinds of non-modal categorical proposition and their
ingredients [Peter of Spain T I.8-9 (4)]:
available later.
3 Opinions differed on whether there are also mind-independent entities corresponding to
propositions. For many medievals, propositions are tokens, not types, and this is important
in certain cases, such as addressing semantic paradoxes, where two tokens of the same type
might differ in truth value. But for the most part nothing would be changed in the theory if
propositions were types.