Chiasmus
A figure in which words or ideas are repeated in reverse order across two balanced parts.
Chiasmus mirrors a structure so the second half inverts the first, as in “ask not what your country can do for you—ask what you can do for your country.” Writers use it to create memorable symmetry and to sharpen a contrast or turn a phrase back on itself. The crossing pattern gives statements a sense of neat, closed logic.
Example
Satan’s reasoning that it is “better to reign in Hell than serve in Heaven” leans on inverted balance to make his defiance sound like wisdom.
Paradise Lost · John Milton