Morgan Meis in The Easel:
The painting is known as Woman in Grey Reclining. It was painted in 1879. It depicts a woman in a lovely dress reclining on a couch. Does she have a white flower on the left strap of her dress? Maybe. Probably. We cannot be completely sure. That’s because much of the detail in the painting is only hinted at by the brushwork. A few dabs of white paint here. A few daubs of grey over there. A stroke of black across the neck, giving us the sense of a choker. We’ve come to call this kind of painting impressionist. The term was originally meant as an insult. But it stuck and became a moniker of pride, as often happens with insults.
I’m interested in a very specific part of this painting. It’s an area of paint in the middle right side of the painting (from the viewer’s perspective), the smudgy area of white and grey over the top of the couch just beyond the woman’s arm. Do you see it? What is that smear doing there? It’s not part of the couch. And it’s not part of the woman’s dress. Nor does it belong to the wall. It’s quite disconcerting when you really focus on it.
More here.