"Only through education does one come to be dissatisfied with his own knowledge,
and only through teaching others does one come to realize the uncomfortable inadequacy of his knowledge.
Being dissatisfied with his own knowledge,
one then realizes that the trouble lies with himself,
and realizing the uncomfortable inadequacy of his knowledge one then feels stimulated to improve himself.
Therefore, it is said, "the processes of teaching and learning stimulate one another."
Confucius, circa 500 BCE
It is the supreme art of the teacher to awaken joy in creative expression and knowledge.
Albert Einstein 1940