ABSTRACT
We characterize those small categories with the property that flat (contravariant) functors on them are coherently axiomatized in the language of presheaves on them. They are exactly the categories with the property that every finite diagram into them has a finite set of (weakly) initial cocones.
ACKNOWLEDGMENT
Supported by the Ministry of Education of the Czech Republic under the project MSM 143100009.
Notes
#Communicated by R. Wusbauer.