Three sleepless nights I passed in sounding on, Through words and things, a dim and perilous way.

The intellectual power, through words and things, Went sounding on, a dim and perilous way!

I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use.

Thou living ray of intellectual fire.

Our intelligence cannot wall itself up alive, like a pupa in a chrysalis. It must at any cost keep on speaking terms with the universe that engendered it.

In the practical use of our intellect, forgetting is as important as remembering.