I bid the chords sweet music make, And all must follow in my wake.

Ye great teachers: listen to what you say!

All ages have said and repeated that one should strive to know one's self. This is a strange demand which no one up to now has measured up to and, strictly considered, no one should. With all their study and effort, people are directed to what is outside, to the world about them, and they are kept busy coming to know this and to master it to the extent that their purposes require. . . . How can you come to know yourself? Never by thinking, always by doing. Try to do your duty, and you'll know right away what you amount to. And what is your duty? Whatever the day calls for.

As soon as any one belongs to a narrow creed in science, every unprejudiced and true perception is gone.

Every second is of infinite value.

Should I not be proud, when for twenty years I have had to admit to myself that the great Newton and all the mathematicians and noble calculators along with him were involved in a decisive error with respect to the doctrine of color, and that I among millions was the only one who knew what was right in this great subject of nature?

We can redeem anyone who strives unceasingly.