And Archimedes, as he was washing, thought of a manner of computing the proportion of gold in King Hiero's crown by seeing the water flowing over the bathing-stool. He leaped up as one possessed or inspired, crying, "I have found it! Eureka!".
PlutarchIf you hate your enemies, you will contract such a vicious habit of mind that it will break out upon those who are your friends, or those who are indifferent to you.
Plutarch