Nature is trying very hard to make us succeed, but nature does not depend on us. We are not the only experiment.
– R. Buckminster Fuller

Here is another one:

We are not going to be able to operate our Spaceship Earth successfully nor for much longer unless we see it as a whole spaceship and our fate as common. It has to be everybody or nobody.

But how wrong he was about this one:

By 2000, politics will simply fade away. We will not see any political parties.