This paper presents a new algorithm for correcting incorrect line drawings—incorrect projections of a polyhedral scene. Such incorrect drawings arise, e.g., when an image of a polyhedral world is taken, the edges and vertices are extracted, and a drawing is synthesized. Along the way, the true positions of the vertices in the 2D projection are perturbed due to digitization errors and the prepro...

1 Norms It is correct to believe that Steinbeck wrote East of Eden, incorrect to believe that Updike wrote Cannery Row. It is right to believe that tomatoes are a fruit, wrong to believe that apples are a vegetable. More generally, true beliefs are correct or right, false beliefs are incorrect or wrong. This suggests that a norm of truth governs the state or attitude of belief. Since it is wron...