"It constantly remains a source of disappointment to me that my drawings are not yet what I want them to be. The difficulties are indeed numerous and great, and cannot be overcome at once. To make progress is a kind of miner’s work; it doesn’t advance as quickly as one would like, and as others also expect, but as one stands before such a task, the basic necessities are patience and faithfulness. In fact, I do not think much about the difficulties, because if one thought of them too much one would get stunned or disturbed."