Whatever you cannot understand, you cannot possess.

Most pioneers are at the mercy of doubt at the beginning, whether of their worth, of their theories, or of the whole enigmatic field in which they labour.

Men are much more apt to agree in what they do than in what they think.

To have more, you must first be more.

What must the English and French think of the language of our philosophers when we Germans do not understand it ourselves?

Yet through delivery orators succeed, I feel that I am far behind indeed.

If you don't feel it, you'll never achieve it.