World War III will be fought,
but World War IV
will be fought with
sticks and stones.
I never think of the future.
It comes soon enough.
Only two things are infinite, the universe and human stupidity,
and I'm not sure about the former.
We can't solve problems by using the same kind of thinking we used when we created them.
If you can't explain it simply,
you don't understand it well enough.
Common sense is the collection of prejudices acquired by age eighteen.