External conditions can, to a certain extent, reduce, but never cancel individual repsonsibility.

What is essential in the life of a man of my kind is what he thinks and how he thinks, and not what he does or suffers.

Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted.

Rejoice with your family in the beautiful land of life.

Imagination without knowledge may create beautiful things, knowledge without imagination can create only perfect ones.

Conventional words or other signs have to be sought for laboriously only in a second stage, where the associative play already referred to is sufficiently established and can be reproduced at will.

There is possibility in every difficulty.