Page History

...

Concretes may be distinguished as being of three types: (1) events; (2) individuals (including existents); and (3) aggregates.

...

The distinctive unity of an event is constituted by its strict identity as an event. Its identity is strict because it has, or is essentially qualified by, all of its properties

The distinctive unity of an individual, on the other hand, is constituted by its genetic identity as an individual. Its identity is genetic because it has, or is essentially qualified by, only some of its properties, while it has or is qualified by other of its properties only accidentally. Thus, even if it had many different properties from those it in fact has, it would still be the same individual.

The distinctive unity of an individual, on the other hand, is constituted by its

An aggregate is distinguished from a singular, whether event or individual, because it has relatively less unity as an aggregate than any of the singulars comprised within it. It has relatively less unity than any of the singulars comprising it because such unity as it has is neither the strict identity of an event nor the genetic identity of an individual. 

Therefore, although all types of concretes are both one and many, each type of concrete is both one and many in its own distinctive way. An event is one and many in the distinctive way constituted by its strict identity as an event; that is to say, it so has, or is so essentially qualified by, all of the many other events and properties to which it is internally related that if even a single element in this many were otherwise, it would have different properties and would therefore be be a different event. An individual, by contrast, is one and many in the distinctive way constituted by its genetic identity as an individual; that is to say, it so has, or is so essentially qualified by, only some of the many other events and properties to which it is internally related that it would still be the same individual evenif even if other of these events and properties were different and it therefore had many different properties from those it in fact has. Finally, an aggregate is one and many in the distinctive way constituted by its having neither the strict identity of an event nor the genetic identity of an individual. 

...