Unfinished, or when is a painting finished?

The new Met Breuer exhibit, "Unfinished" was intriguing and thought-provoking. I recommend it highly (although I admit that I never got beyond the 3rd floor where the older paintings are exhibited). For one thing, I was surprised that nearly all the paintings had areas nearly finished and other areas barely touched.

I was mostly "taught" (that may be a stretch, since I have taken only maybe two or three real painting teachers and learned a lot by watching others and reading "how to" books) that one should work on all areas of a painting to the same level of finish before getting too caught up in the details. The idea is to get your composition set up and most of your general dark and light areas established first, because without that you won't have a good painting. Perhaps this doesn't apply once you are a "master" with works being shown in major museums! 

In general, however, the question always persists about when is a painting "finished." It is a common topic in my studio, which I share with another painter whose work is looser and more expressionistic than mine.  We often ask each other's opinion on many aspects of our paintings - are there color or tonal issues, how can I solve this drawing problem - but the most common one is "Does it look finished to you." And it's usually because she and I differ in our approaches to our paintings. I tend towards thinking something is done, driven by a desire for conclusion. She tends towards wanting to continue working on a painting, driven by a sense of possibilities. Because I trust her judgment (she's almost always right!), I'll take a deep breath and continue on, and sure enough I reach a point when the painting is at a better state.

That better state, being considered "finished," is hard to describe. For me, there's a balance of light and shadow, color harmony, a sense of balance among all parts of the painting, the composition reads clearly but not so blatantly that it's boring. One way to understand this is to document a painting in progress. I do that occasionally and share it on social media (Facebook, Instagram, Twitter). 

Here are stills of one painting's progress:

Unfinished, right?! Yes, there's more to be done on this painting. Or should I leave it as is for posterity to let future art historians guess whether or not it's finished? Stay tuned!