You imagine that I look back on my life's work with calm satisfaction. But from nearby it looks quite different. There is not a single concept of which I am convinced that it will stand firm, and I feel uncertain whether I am in general on the right track.

It is both auspicious and peaceful for people to choose vegetarinism.

Agreements about what is good or not, are usually not worth much. It is very much like art, is it not an art to lead a good life?

Things you can get access to, you should never memorize.

Fantasie is belangrijker dan kennis, want kennis is begrensd.

The most beautiful gift of nature is that it gives one pleasure to look around and try to comprehend what we see.

There is nothing divine about morality, it is a purely human affair.