Better keep yourself clean and bright; you are the window through which you must see the world.
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.
Progress is impossible without change, and those who cannot change their minds cannot change anything.
A life spent making mistakes is not only more honourable, but more useful than a life spent doing nothing.
We don't stop playing because we grow old; we grow old because we stop playing.
The reasonable man adapts himself to the world: the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.
Animals are my friends...and I don't eat my friends.
You see things; you say, 'Why?' But I dream things that never were; and I say 'Why not?
Make it a rule never to give a child a book you would not read yourself.
A life spent making mistakes is not only more honorable, but more useful than a life spent doing nothing.