We pass the word around; we ponder how the case is put by different people, we read the poetry; we meditate over the literature; we play the music; we change our minds; we reach an understanding. Society evolves this way, not by shouting each other down, but by the unique capacity of unique, individual human beings to comprehend each other.
Music is the effort we make to explain to ourselves how our brains work. We listen to Bach transfixed because this is listening to a human mind.
We are a spectacular, splendid manifestation of life. We have language. . . . We have affection. We have genes for usefulness, and usefulness is about as close to a 'common goal' of nature as I can guess at.