The one unpardonable fault is bad work.

And here I would remind you of a thing essential to our art, which you will certainly not ignore, and to which I believe you attach the full importance it deserves.

In every kind of plastic work we ought to strive with all our might at making what has cost time and labour look as though it had been produced with facility and swiftness.

It sometimes happens, but rarely, that a portion of our work turns out excellent with little pains bestowed upon it.

Most frequently, however, it is the expenditure of care and trouble which conceals our toil.