Complex Predications 133
For it determines that the word ‘man’, for example, is complex: the word may
have no evident parts to it; but it is definable—as ‘rational mortal animal’ (vel
sim)—and for that reason it is complex. If that line of inquiry is pursued, it
will turn out that—if Aristotle’s theory is true—there are exactly ten simple
predicates: ‘substance’, ‘quantified item’, ‘qualified item’, and so on. Now
some ancient texts do indeed hint at that conclusion; but it does not answer
to anything in Aristotle—or in Plotinus, or in Porphyry.
Aristotelians thus need to distinguish the simplicity of ‘man’ from the
complexity of ‘featherweight’. They thought to do so by declaring that the
former, but not the latter, signifies ‘one thing’—that it signifies some single
or unified item. The definitional formula for ‘man’, namely ‘rational mortal
animal’, is semantically complex; but the term and its definition signify a
unity and for that reason, or in that sense, the term is not complex. The
definitional formula for ‘featherweight’ not only is complex: in addition, it
signifies a plurality, or at least a non-unity—featherweights tend to crack up.
But under what conditions does a term or a formula signify a unity? Not
even Aristotle managed to give a satisfactory answer to the question.
As Plotinus mercilessly demonstrated, the Aristotelian classification of
predicates—the so-called ‘doctrine of the categories’—is a quagmire; and
any account of predication which is built upon that doctrine must wobble.
If you take the Categories to be the first part of a unitary Organon,andif
you suppose that the ‘doctrine of the categories’ prepares the ground for the
‘doctrine of the syllogism’ which the Prior Analytics presents, then you are up
the creek—and paddleless.
Happily, the central part of the Categories, in which the ‘doctrine of the
categories’ is developed, has nothing to do with the logic of the Analytics.Of
course, Aristotle’s syllogistic is essentially tied to the concept of predication; for
the argument forms which it examines are fixed by a certain logical structure,
namely the subject–predicate structure. But nothing in the syllogistic requires,
or even suggests, any classification of predicates: that a predicate is substantial
or qualitative, relational or a matter of habitus —all that is of supreme
indifference to the syllogistic. There is no difference whatever, from a
syllogistic point of view, between ‘Every man is an animal’, where the
predicate is substantial, and ‘Every man is less than ten feet tall’, where the
predicate is quantitative.
I do not mean that no classification of predicates could be of pertinence to
any theory of inference. I do not even mean that Aristotle’s classification of
predicates has no logical interest. I mean, simply and indisputably, that the