An object will display the greatest difference of light and shade
when it is seen in the strongest light, as by sunlight, or, at
night, by the light of a fire. But this should not be much used in
painting because the works remain crude and ungraceful.
An object seen in a moderate light displays little difference in the
light and shade; and this is the case towards evening or when the
day is cloudy, and works then painted are tender and every kind of
face becomes graceful. Thus, in every thing extremes are to be
avoided: Too much light gives crudeness; too little prevents our
seeing. The medium is best.