I found this poem by Bertolt Brecht, a German writer. It's short and simple, but provocative:
General, your tank
is a powerful vehicle
it smashes down forests
& crushes a hundred men.
but it has one defect:
it needs a driver.
General, your bomber is powerful
it flies faster than a storm
& carries more than an elephant.
but it has one defect:
it needs a mechanic.
General, man is very useful.
He can fly & he can kill.
but he has one defect:
He can think.
There's another quote that's variably attributed to Brecht, or Vladimir Mayakovsky, that I found interesting: "Art is not a mirror to hold up to society, but a hammer with which to shape it."