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