The predicables, unlike the categories, express the relation of a predicate term to its subject in a proposition.

They apply to universal concepts (classes) and not individuals.

  • Genus

Is the ‘note’ of essence that is common to all of its subspecies.  Example:  A Bus is a Truck

  • Specific Difference

This distinguishes a species from all other species in its genus.

  • Species

What individuals (instances – both form and quantity) have in common with their class (form only).

  • Property

Property flows necessarily from essence.  Wherever that class extends, so does this property.  It is, however, not a specific difference or part of the essential definition of that class.

  • Accident

Exists only contingently.  They may or may not accompany the essential presence of the predicated subject.