The Republic by Plato Part 8 Page 45

And when they meet in private will not people be saying to one another ‘Our warriors are not good for much’?

Yes, he said, I am quite aware that this is their way of talking.

And, as in a body which is diseased the addition of a touch from without may bring on illness, and sometimes even when there is no external provocation a commotion may arise within — in the same way wherever there is weakness in the State there is also likely to be illness, of which the occasion may be very slight, the one party introducing from without their oligarchical, the other their democratical allies, and then the State falls sick, and is at war with herself; and may be at times distracted, even when there is no external cause.

Yes, surely.