Perhaps this implies a sort of insulated creative world, full of personal mythology. Not necessarily a misanthropic person or a hermit.

I use the term, as Gopnik uses it, loosely; well aware of the contradictions. After all, no person (or artist) is just one thing or the other.

Although you qualify it somewhat, I think it is wrong to refer to Cornell as a reclusive artist. As Gopnik points out, Cornell regularly received visitors at the house on Utopia Ave. (he always offered them little coffee cakes); he was regularly exhibited and attended openings; and he carried on extensive correspondences. A better term, I think, would be “solitary artist.” “Reclusive” suggests an active avoidance of human contact, and this certainly wasn't the case for Cornell. Rather, a combination of family obligation and his own quiet, contemplative nature kept him on the periphery of the New York art world that others hungrily dove into.

There are a number of keys to understanding Cornell's work. In fact, “understanding” is probably not the best word, as Cornell never intended his boxes to mean anything. They are meant to be inhabited and experienced, not understood. One key that you mention here is the sense of longing and nostalgia. There is also a sense of narrative in his work. You have a feeling that a story is being told but that it is only being presented to you in enigmatic vignettes. It is no surprise that Cornell is frequently cited by poets and writers as a favorite artist.

The narrative being hinted at, though, is deeply personal. I consider Cornell to be the most personal (and literary) of modern American artists. Meaning cannot be extracted from Cornell's work because it is hermetic, a bell jar enclosing a swirling universe of interacting, recurrent images, sealed off from the mundane world the rest of us inhabit.

Perhaps the best way to enter Cornell's world is to see it as a modern Wunderkammer, a Cabinet of Curiosities, little wonders and gems and oddities, each displayed in a little drawer or box and suggesting the vast marvel of the Universe itself. Seen this way, Cornell's boxes are no longer understood as discrete works of art but as pieces of a grander, personal cosmos. And here we must include in this cosmos the workshop where he created, with its hand-labeled boxes full of sundry components and its file cabinets filled with dossiers of clippings from celebrity magazines and old books and maps. (The workshop is now housed in its entirety in the Smithsonian.) And we must also include the voluminous, dreamlike diaries he kept (selections from which can be found in Mary Ann Caws' “Joseph Cornell's Theater of the Mind”.) For these are as much his art as the boxes are. They are of a piece, forever talking to each other in a language that sounds familiar but which we can never translate.