Wikipedia:

Hayao Miyazaki is a prominent Japanese filmmaker and producer whose animated works are characterised by several recurring themes and motifs.

Many of these recurrent features are notable for being so uncommon in the medium, for example the lack of evil or villain characters, the advocacy of a pacifist ethic and prominence of feminism. Other features are more notable for being personal idiosyncrasies, such as the obsession with flight and the symbolism of water. The formal emphasis placed on these various elements constitutes a running discourse that transcends the individual works and creates a larger, ongoing meta-narrative.

Really good article. Also Miyazaki is literally the best. Just the best.