Chiasmus..es

The OED defines "chiasmus" as, "A grammatical figure by which the order of words in one of two of parallel clauses is inverted in the other."
chiasmus.com

Some fine examples:
“Never be haughty to the humble; never be humble to the haughty.”- Jefferson Davis

“If thought corrupts language, language can also corrupt thought.”- George Orwell

“Life creates order, but order does not create life.”- Antoine de Saint-Exupéry

“Poetry is the record of the best and happiest moments of the happiest and best minds.”- Percy Bysshe Shelley

“People crushed by law have no hopes but from power. If laws are their enemies, they will be enemies to laws.”- Edmund Burke

“By the way, I heard an answer today to the platitude: ‘There's no money in poetry.’
It was: ‘There's no poetry in money, either.’”- Robert Graves

“In the Halls of Justice the only justice is in the halls.”- Lenny Bruce

“People in cars cause accidents and accidents in cars cause people.”- Garrison Keillor

“You have to know how to accept rejection and reject acceptance.”- Ray Bradbury