We don't stop playing because we grow old; we grow old because we stop playing.

More from George Bernard Shaw

• An election is a moral horror, as bad as a battle except for the blood; a mud bath for every soul concerned in it.
• Do you know what a pessimist is? A man who thinks everybody as nasty as himself, and hates himself for it. An Unsocial Socialist (1950)
• There are two tragedies in life. One is not to get your heart's desire. The other is to get it.
• There are two tragedies in life. One is to lose your heart’s desire. The other is to gain it.
• The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.
• There is only one religion, though there are a hundred versions of it.