Polypton is a word scheme that plays with derivative forms of the same word.
FDR offers a famous example in his claim that the “only thing we have to fear (1) is fear (2) itself.”
Fear #1 is a verb in infinitive form, while fear #3 is a noun. Both words, of course, share an etymological root. The polypton here shades toward the paradoxical, setting up FDR to explain:
So, first of all, let me assert my firm belief that the only thing we have to fear is fear itself—nameless, unreasoning, unjustified terror which paralyzes needed efforts to convert retreat into advance.
Polypton can also create a reinforcing effect, as in Lord Acton’s “absolute power corrupts absolutely..”
Taylor Coe 