Chapter 3: The Categories & the Predictables
April 24, 2012 | by Dunstan
Notes re: Scott Sullivan's An Introduction to Traditional Logic
– Primary substance is an individual existent, e.g., Socrates
– Primary substance is not a category
– Primary substance does not exist in something
– Secondary substance is universal or nature, e.g., human being
– Secondary substance is a category
– Secondary substance is predicated of a primary substance
– Modify the way a primary substance exists
– Exist only in primary substances
– Ten categories = secondary substance + nine accidents
– Is a secondary substance an accident, i.e., does a secondary substance modify the way something exists?
o No, because an individual existent (a primary substance) has the kind of existence which it has as a specific kind of existing being only through a secondary substance.
o This is perhaps the sense in which we should take Sullivan’s assertion that the secondary substance is the main category (existing as a universal predicate)
Predicables Understanding Predicables
– If categories are the predicates of a subject, then the predicables are the ways in which the predicates are related to a subject
– Genus + specific difference = species
– Is every species a secondary substance?
– Is a genus ever a secondary substance?
o Sullivan characterizes both species and secondary substance as the “nature” of a thing
o Sullivan also characterizes “living” as a species (of corporeal things)
o But “human being” and “living” are not species in the same sense or to the same degree
o “living” doesn’t get as close as “human being” to revealing the reality of Socrates
o Is Sullivan using species in an equivocal way?
§ To refer to the nature of an existent (i.e., a primary substance) AND
§ To refer to a subclass of a larger class?
– Characteristic that always accompanies a particular nature
– Distinguished from accident, which is a characteristic that can be said of things with different natures