JOHN DONNE

No man is an island, entire of itself;
every man is a piece of the continent, a part of the main.
If a clod be washed away by the sea, Europe is the less,
as well as if a promontory were, as well as if a manor of thy friend's or of thine own were:
any man's death diminishes me, because I am involved in mankind,
and therefore never send to know for whom the bell tolls;
it tolls for thee.