On the surface, this poem is about Yu Shinan, but what philosophy does it actually contain?

Dewdrops drop, and sparse tung flows out. Cicada is far away from cicada because cicada is on a tall tree, not relying on autumn wind. On the surface of this poem, cicadas sing far and wide. Most people often think that cicadas spread far because of the autumn wind, but in the poet's view, they are aloof and self-sufficient It contains such a philosophy: people with high moral character can be famous without the help of external forces.