According to Heidegger ("The Origin of the Work of Art"), what is the difference between "thing" and "work"?
The difference is that artworks establish comprehensive worlds that unify entire peoples, whereas things organize smaller and more intimate local worlds.
Artworks in Heidegger’s sense include the ancient Greek temples at Paestum, the Bamberg Cathedral, Homer’s Iliad and Odyssey, and Virgil’s Aenead. Heidegger imagines a jug and an old stone bridge as things in his sense.
When artworks are working, they stand out dramatically from their surroundings. When things are thinging they often do so unobtrusively. A bridge over a stream or a town square draw from us certain attitudes and orient us in specific ways. If these things are a familiar part of our lives, we take them into account in the ways required even when we are not aware of doing so.
One of the interesting paradoxes of art is that it can bring to light the unobtrusive thinging of things. Heidegger discusses a painting by Vincent van Gogh of what he takes to be peasant shoes, which reveals the ordinary and simple reliability of the latter.
I like to think in this context about Wallace Stevens’s “Anecdote of the Jar.”
I placed a jar in Tennessee,
And round it was, upon a hill.
It made the slovenly wilderness
Surround that hill.
The wilderness rose up to it,
And sprawled around, no longer wild.
The jar was round upon the ground
And tall and of a port in air.
It took dominion everywhere.
The jar was gray and bare.
It did not give up bird or bush,
Like nothing else in Tennessee.
Stevens’s jar doesn’t jar in the way that Heidegger’s jug, for example, jugs, either by pouring water that quenches mortals or wine that enlivens them, or by pouring a libation to the gods. Instead, it brings order, wholeness, and humanity to an otherwise unorganized and uninhabited place. In this way, it’s working a bit like an artwork, but it retains the intimacy and locality of a thing.