A Treatise on Painting
by Leonardo da Vinci, translated by John Francis Rigaud
Accuracy ought to be learnt before Dispatch in the Execution
4009421A Treatise on Painting — Accuracy ought to be learnt before Dispatch in the ExecutionJohn Francis RigaudLeonardo da Vinci

Chap. CLXXXI.Accuracy ought to be learnt before Dispatch in the Execution.

If you wish to make good and useful studies, use great deliberation in your drawings, observe well among the lights which, and how many, hold the first rank in point of brightness; and so among the shadows, which are darker than others, and in what manner they blend together; compare the quality and quantity of one with the other, and observe to what part they are directed. Be careful also in your outlines, or divisions of the members. Remark well what quantity of parts are to be on one side, and what on the other; and where they are more or less apparent, or broad, or slender. Lastly, take care that the shadows and lights be united, or lost in each other; without any hard strokes, or lines: as smoke loses itself in the air, so are your lights and shadows to pass from the one to the other, without any apparent separation.

When you have acquired the habit, and formed your hand to accuracy, quickness of execution will come of itself[1].

  1. Sir Joshua Reynolds frequently inculcated these precepts in his lectures, and indeed they cannot be too often enforced.