do you know of any poetic devices in "the soul selects her own society" besides alliteration?

Answer 1

Personification--the attribution of human characteristics to non-human elements ("The hills have eyes").

Synecdoche--the use of a representative portion of a thing as a name for the whole ("I got a new set of wheels").

Metonymy--the substitution of one word for another with which it is associated ("The bench" referring to a court of law).

Answer 2

Perhaps metaphor. 'The water is a mirror'.

Not simile, though. That would be 'The water was like a mirror'.

(Note: Whether it would qualify as a metaphor would depend on how literally you think about souls.)

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