Heaven, in the production of things, is sure to be bountiful to them, according to their qualities. Hence the tree that is flourishing, it nourishes, while that which is ready to fall, it overthrows.

Excessive (population) growth may reduce output per worker, repress levels of living for the masses and engender strife

Shall I tell you what knowledge is? It is to know both what one knows and what one does not know.

One who can move mountains start with the little stones.

Bird in hand makes it harder to blow nose.

Who keeps the old akindle and adds new knowledge is fitted to be a teacher.

Learning without thought is labor lost; thought without learning is perilous.