Art historians tend to see Rembrandt’s method as an attempt at naturalism, but it goes much farther than portrait conventions have ever gone, then or since. Consider what is happening in the paint, aside from the fact that it is supposed to be skin. Paint is a viscous substance, already kin to sweat and fat, and here it represents itself: skin as paint or paint as skin, either way. It’s a self-portrait of the painter, but it is also a self-portrait of paint. The oils are out in force, like the uliginous oozing waters of a swamp bottom. The paint is oily, greasy, and waxy all at once — even though modern chemistry would say that is impossible. It sticks: it is tacky and viscid like flypaper. It has the pull and suction of pine sap.
Over the far cheek, it spreads like the mucilage schoolchildren use to glue paper, resisting and rolling back. On the nose — it’s rude, but appropriate — the paint is semi–solid, as if the nose were smeared with phlegm or mucus. On the forehead, it looks curdled, like gelatin that is broken up with a spoon as it is about to set. There is drier paint around the eyes, and the bags under the eyes are inspissated hunks of paint, troweled over thin, greyish underpainting. The grey, which is left naked at the corner of the eye and in the folds between the bags, is the imprimatura, and the skin over it is heavy, thick, and clammy. The same technique served for the wings of the nose, where dribbles of paint come down to meet the nostril but stop short, leaving a gap where the grey shows through. Of course the nostril is not a hole, but a plug of Burnt Sienna with Lamp Black, and it also lies on top of the grey imprimatura. Rembrandt’s thin mustache is painted with wiggles of buttery paint, almost like milk clinging to a real mustache.
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