... and there's another, harder, higher way to think about this "sphere of art."
It's when you consider that aforementioned need as a kind of ethical command. A mysterious moral absolute.
This, to me, is what distinguishes "professional writers" from those who think writing means being part of some kind of special, challenged "community". Certainly, writers are part of the commonweal, and speak for it, and to it; but this implies that the speaking is not simply an end in itself. Goodby forever, poetry clubs & committees.
The "commerce" of art & writing is not a quantifiable mass or entity; it's a spiritual or moral quality. It's a demand on the writer - a force of conscience - impelling him or her to address, and condemn, some moral danger, challenge, extremity, debasement : or, on the other hand, it's an undeniable impulse to praise and celebrate some good thing in life & reality.
These moral acts of conscience are what separate and individuate - utterly, indubitably - because they are the substance of the work, its motive - each piece of writing, and each writer's specific "job of work", inspiration, calling. & this element of the whole business is what makes me cast my famously sceptical eye on literary group activities. It's not that I consider myself more correct or moral or effective - I do not, in any way; it's that I'm pointing out an aspect which I recognize & believe exists in the larger phenomenon of writing as a whole.