Unless you try to do something beyond what you have already mastered you will never grow. - Ralph Waldo Emerson

Money often costs too much.

Thought is all light, and publishes itself to the universe. It will speak, though you were dumb, by its own miraculous organ. It will flow out of your actions, your manners, and your face. It will bring you friendships. It will impledge you to truth by the love and expectation of generous minds. By virtue of the laws of that Nature, which is one and perfect, it shall yield every sincere good that is in the soul, to the scholar beloved of earth and heaven.

A mind might ponder its thought for ages, and not gain so much self-knowledge as the passion of love shall teach it in a day.