A Treatise on Painting, by Leonardo da Vinci
Senex and Taylor, London
The Motions of the Face, occasioned by sudden Agitations in the Mind, are very numerous; the chief are Laughing, Weeping, Shrieking, Singing in several Tones, showing Amazement, Wrath, Joy, Sorrow, Fear, Vexation, Grief, and other the like Motions; all of which we shall have occasion to consider hereafter: As to Laughing and Crying, the Motions they produce in the Face, are very much alike, and the Characters they impress on the Mouth, Cheeks, and Eye-lids, not to be distinguished. Their only difference appears in the Eye-brows, and in the space that separates these from each other, and shall be considered more at large, when we come to treat of the Motions happening in the Face, Hands, and other Members under any sudden surprize. The Knowledge of these Motions is of the last importance to a Painter, and his Figures without this will be dead in a double capa city: Let him beware however, of the other extreme; nor ever make their Motions so affectedly animated, as to represent the Ferment of a Battle in a Scene of calmness and composure, or the Fury of a Bacchanal, or fantastick gestures of a Harlequin in a Subject which requires Sobriety and Peace. Observe further, that those whom you introduce as present at the Action you exhibit, be attentive to what passes, with Countenances and Behaviour, full of Admiration, Reverence, Grief, Distrust, Fear, or Joy, as shall be most suitable to the Subject, and to the Persons forming the Assembly.