A Treatise on Painting/Chapter 114
Appearance
Chap. CXIV.—Of the Boundaries of Objects called Outlines or Contours.
The outlines or contours of bodies are so little perceivable, that at any small distance between that and the object, the eye will not be able to recognise the features of a friend or relation, if it were not for their clothes and general appearance. So that by the knowledge of the whole it comes to know the parts.