Important distinction: this is an epistemic "can", not a deontic "can". In other words, they are saying that it is possible to keep your windows open if you wa

Important distinction: this is an epistemic "can", not a deontic "can". In other words, they are saying that it is possible to keep your windows open if you want to and still not let noise in--not that you are permitted to cancel the noise, but must keep your windows open anyway. I had initially thought this would be something about indoor CO2 buildup or something, but no.