Date: 1691

"And besides who knows but the Same Observation may hold true in Men, which is in Metals, That those of the strongest and noblest Substance, are hardest to be Polisht."

— Blount, Thomas Pope, Sir (1649-1697)

Date: 1766

"I know not whether the remark is to our honour or otherwise, that the lessons of wisdom have never such a power over us, as when they are wrought into the heart, through the ground-work of a story which engages the passions: Is it that we are like iron, and must first be heated before we can be ...

— Sterne, Laurence (1713-1768)