The difference between stupidity and genius is that genius has its limits.
I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.
I am not only a pacifist but a militant pacifist. I am willing to fight for peace. Nothing will end war unless the people themselves refuse to go to war.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
The significant problems we face cannot be solved at the same level of thinking we were at when we created them.