Who said "The empire that understands itself will endure."?

This quote is attributed to Hadrian.

The empire that understands itself will endure. - Hadrian

"The empire that understands itself will endure."

Hadrian

Emperor Ancient Rome 76–138

"Nothing is harder to bear than a good example."

"I have always strived to be the best, but I have also learned that the best is not always perfection."

"A man who fears nothing is more dangerous than a man who fears something."

"The greatest luxury is knowledge."