No one can understand love who has not loved and been loved; no one can comprehend sorrow who has not had the companionship of sorrow.

The experiment has been made in many forms, but no one has yet been nourished by the fruit of the tree of knowledge who has eaten of that fruit alone.

In the art of living, as in all the arts which illustrate and enrich living, the amateur and the dilettante have no real position; they never attain to that mastery of knowledge or of execution which alone give reality to a man's life or work.

Mastery in any art comes to those only who give themselves without reservation or stint to their task; mastery in the supreme art of living is within reach of those only who live completely in every faculty and relation.
To stand in the closest and most vital relation to one's time is, therefore, the first condition of comprehending one's age and getting from it what it has to give.

But while a man must be in and with his time in the most vital sense, he must not be wholly of it.