He knows not his own strength who hath not met adversity.

He knows not his own strength that hath not met adversity.

He knows not his own strength that has not met adversity.

He who has so little knowledge of human nature as to seek happiness by changing anything but his own disposition will waste his life in fruitless efforts.

It is a wise father that knows his own child.

All travel has its advantages. If the passenger visits better countries, he may learn to improve his own. And if fortune carries him to worse, he may learn to enjoy it.