Final answer:
The quote in question is spoken by Enobarbus in Shakespeare's play Antony and Cleopatra, and it reflects on the social strategies related to the choice of companions.
Step-by-step explanation:
The quote "A nice and subtle happiness I see / Thou to thyself proposest, in the choice / Of thy associates..." is spoken by the character Enobarbus in William Shakespeare's play, Antony and Cleopatra. Enobarbus is Antony's loyal friend and serves as a sort of commentator throughout the play, often providing a clear-sighted view of events and characters. The quoted lines suggest that he perceives someone is planning to derive pleasure from the company they keep, reflecting on the subtle joys and strategies implicit in social relationships.