Sign of maturity: When you find something unpleasant floating in a cup of coffee that had been left out overnight, you do not take a picture and send it to your housemates. You simply clean the cup.
Sign of the current limits of said maturity: After thoroughly cleaning the cup, however, you do consider telling your housemates about what you found, just not telling them which cup it was.
Sign of maturity: You do not actually do this.
Proviso: Intentionally.
Sign of maturity: You are mildly horrified to realize that as you are in the process of telling this story to one of your housemates, she has poured herself a fresh cup of coffee and commented that, “This coffee taste’s different, good, but different.”
Sign of the current limits of said maturity: Despite your horror, you manage to casually tell her, “Maybe that’s because the cup you’re using is the cup I was telling you about.”
Sign that maturity is overrated: She favors you with a truly delighted smile and says, “I thought it tasted nutty!”