In William Congreve’s The Way of the World identify the speaker of the line : "One’s cruelty is one’s power, and when one parts with one’s cruelty, one parts with one’s power."
The specific quote, "One’s cruelty is one’s power, and when one parts with one’s cruelty, one parts with one’s power," is spoken by Millamant in William Congreve’s play, *The Way of the World*.
This line is characteristic of Millamant's personality and her approach to relationships, particularly her interactions with Mirabell. The quote emphasizes her understanding of power dynamics within social and romantic contexts.
Therefore, the speaker of the quote is indeed Millamant.