|
An initial object in a category
is an object in
such that, for every object in
, there is exactly one morphism
.
A terminal object in a category
is an object in
such that, for every object in
, there is exactly one morphism
.
A zero object in a category
is an object 0 that is both an initial object and a terminal object.
All initial objects (respectively, terminal objects, and zero objects), if they exist, are isomorphic in
.
|