Once a man and his son were walking along the beach.  As they walked, they noticed the many starfish that the incoming tide had left stranded on the shore.  The child repeatedly knelt, picked up a starfish, and tossed it back into the sea.  Finally, the father said to the boy, "Son, don't bother throwing each starfish back.  There are so many, and you can't save them all.  You're just wasting your time.  What you're doing doesn't really matter."  The boy knelt, selected another starfish and replied, "But it matters to this one."