Meton (astronomer in 5th century BC): With the straight ruler I set to work To make the circle four-cornered .
The truth is forced upon us, very quickly, by a foe.
Men of sense often learn from their enemies. It is from their foes, not their friends, that cities learn the lesson of building high walls and ships of war.
By words the mind is winged.
Evil events from evil causes spring.
The old are in a second childhood.