INFLUENCES:

nature

(the shape of a flower, the sound of a brook, the force of a storm, the complexity of cognitive processes)

art itself

(e.g. a particular quintet, melodic gesture, painting, short story plot)

see for example my list of  favourite works

specific techniques / concepts / approaches used by an artist or group of artists

as expressed through works

as expressed through words by the artist(s)

as deduced/proposed /surmised / imposed by analysts, critics, historians, etc.

philosophies/aesthetics/attitudes

(usually but not always in the context of art)

as expressed through works
as expressed through words by the artist
as deduced/proposed /surmised / imposed by analysts, critics, historians, etc.

life itself  (as I perceive it)

appreciation of an event,analysis of specific situations, mental comparison of apparently unrelated things

etc ....