"Then, quite soon, the drawing reached its point of CRISIS. Which is to say that what I had drawn began to interest me as much as what I could still discover. There is a stage in every drawing when this happens. And I call it a point of crisis because at that moment the success or failure of the drawing has really been decided. One now begins to draw according to the demands, the needs, of the drawing. If the drawing is already in some small way true, then these demands will probably correspond to what one might still discover by actual searching. If the drawing is basically false, they will accentuate its wrongness.
"I looked at my drawing trying to see what had been distorted; which lines or scribbles of tones had lost their original and necessary emphasis, as others had surrounded them; which spontaneous gestures had evaded a problem, and which had been instinctively right. Yet even this process was only partly conscious. In some places I could clearly see that a passage was clumsy and needed checking; in others, I allowed my pencil to hover around — rather like the stick of a water-diviner. One form would pull, forcing the pencil to make a scribble of tone which could re-emphasize its recession; another would jab the pencil into restressing a line which could bring it further forward.
"Now when I looked at the model to check a form, I looked in a different way. I looked, as it were, with more CONNIVANCE: to find only what I wanted to find."
From John Berger (2005) Berger On Drawing.