World is a very important term for the earlier Heidegger of Being and Time. OWA is one of the first substantial elaborations of the idea of ‘Earth’ by Heidegger. The term does not survive very long in Heidegger’s philosophy, but it is taken to be a crucial stepping-stone for Heidegger beyond Being and Time toward is later philosophy which is much more poetic in approach, and less concerned with characterizing the nature of human being in the world, and more with large-scale historical changes.
At the very least ‘world’ is how we characterize everything, every thing. If I say, ‘this is the best coffee in the world,’ I am referring to the totality of all things present anywhere on the planet. To this extent, world means present, showing up, there, able to be perceived and used. So the world comprises things, both physical and ideas, that make up the ‘now’ of our existence. In Being and Time Heidegger says something like: the world comprises mini-worlds; those mini-worlds are each more or less coherent places filled with certain kinds of things that enable humans to do certain things. My father’s workshop was a world, filled with woodworking tools and timber and wood shavings and saw dust, etc. Those tools only made real sense in that workshop, the world of that workshop, in which wood-working happens. I would get in big trouble if I took any of them out of there, ‘misplacing them.’ So a is world a relational whole, where things go together, in meaningful and productive ways. Worlds are not just spaces in which a totality of stuff is present, but places in which equipment and materials come together in humanly useful ways.
So later on, Heidegger will use the word ‘open’ more than world. A world is an opening, that is open for things to appear, in ways that open up activities for the humans who also appear there.
Earth is probably the opposite of world. Earth is more like a closing than an opening. It is that into which it seems like things withdraw (and that out of which things some to come, when they appear in the world). This makes it seem very material, in the sense of some earth, soil, rock, rotting matter. It makes it seem dark, where the openness of worlds is more clear and lit. But it also makes it seem active and not just inertly passive; it has an elemental force, a resistance to humans attempting to bring art works forth into the world; and an attraction, a pull, drawing things back into it.
As a notion, earth is there mostly to make artists look more finite, and less like all-powerful geniuses. Artists have to work hard to get things from their returning-to-earth tendencies; but in the end, this labor is never entirely successful. There is no once-and-for-all beyond or out of earth. Things are never entirely here in the world of human activities. They always have aspects or tendencies that are concealed and disappearing or earthly. This is why the work of art is work, working; and this work must continue long after the artist feels like he or she has finished the artwork; the workings of the artwork must be continued, to resist the pull back of the earth. That ongoing work must be done by the artwork itself, and by its ‘preservers’, the institutions founded to keep open the opening that the artwork is making).
In fact, Heidegger seems to say that what makes a work of art a work of art, is that it pays heed to, rather than tries to conceal the concealing, withdrawing, earthly aspects of the artwork, the fact that it can never be all there.
So what might this all mean in practice? Van Gogh’s shoes bring into the world, the world of meaningful things a peasant’s shoes. These things are already in the world, but not normally in such a way as to be perceivable as reliable equipment. To bring this equipmentality into the world, Van Gogh poetizes the shoes. It is not after all a pair of shoes, but instead a mass of dried paint, of smushed oil and stone. The shoes represented in the painting come forth in a particular way because they are not all there; only a certain aspect of the way they shine in the world has been translated into the smushed, dried paint. We can see the wornness of the shoes precisely because they have been painted, because they are halfway between coming forth and withdrawing into mere paint on canvas. The shoes have been brought into the meaningful light of the world only because they are at the same time just the light-on-paint effects of one amongst billions of material things in this world. And this way in which that pair of shoes opens up the world in new ways for us is in the picture Van Gogh painted, but only so long as the painting is treated as an artwork by institution that literally preserves it, and talks about it, interpreting it in new ways, to keep the work it does worlding equipmentality alive.