Why have I not before now finished the miniature I promised to Mrs.
Butts? I answer I have not till now in any degree pleased myself, and
now I must entreat you to excuse faults, for portrait painting is the
direct contrary to designing and historical painting in every respect.
If you have not nature before you for every touch, you cannot paint
portrait; and if you have nature before you at all, you cannot paint
history. It was Michael Angelo's opinion and is mine.
_Blake._