"When you sing with a group of people, you learn how to subsume yourself into a group consciousness because a capella singing is all about the immersion of the self into the community. That's one of the great feelings - to stop being me for a little while and to become us. That way lies empathy, the great social virtue."
Source : William Vickrey, Richard Arnott, Anthony B. Atkinson (1997). “Public Economics: Selected Papers by William Vickrey”, p.432, Cambridge University Press