Knowledge is power. Rather, knowledge is happiness, because to have knowledge -- broad, deep knowledge -- is to know true ends from false, and lofty things from low. To know the thoughts and deeds that have marked man's progress is to feel the great heartthrobs of humanity through the centuries; and if one does not feel in these pulsations a heavenward striving, one must indeed be deaf to the harmonies of life.
Only as you do know yourself can your brain serve you as a sharp and efficient tool. Know your failings, passions, and prejudices so you can separate them from what you see. Know also when you actually have thought through to the nature of the thing with which you are dealing and when you are not thinking at all.
If people can be educated to see the lowly side of their own natures, it may be hoped that they will also learn to understand and to love their fellow men better. A little less hypocrisy and a little more tolerance towards oneself can only have good results in respect for our neighbor; for we are all too prone to transfer to our fellows the injustice and violence we inflict upon our own natures.
Since we can't know what knowledge will be most needed in the future, it is senseless to try to teach it in advance. Instead, we should try to turn out people who love learning so much and learn so well that they will be able to learn whatever needs to be learned.