I'm interested in how few writers cross the osmotic boundaries between science fiction and horror, between genre and what those in genre call mainstream. Or, rather, I should say that I'm fascinated with how many cross and do not return.

Part of it, I think, is the vast difference in states of mind between dreaming the dark dreams of horror and constructing the rational structures of SF, or between tripping the literary light fantastic and being shackled by the gravity of "serious" fiction. It is hard to do both painful to the psyche to allow one hemisphere to become dominant while bludgeoning the other into submission. Perhaps that's why readership of SF and horror, genre and New Yorker fiction overlap less than one would think.

Whatever the reason, it's a pity that more writers feel constrained sometimes by limitations of talent or interest but more frequently by market considerations and the simple fact that they find success in one field to stay in one genre.

Of course, the exceptions are always interesting. George R.R. Martin moves easily between genres and expectations, rarely repeating, always surprising. Dean Koontz left SF just as he was becoming a star there possibly because he sensed his destiny lay in becoming a supernova elsewhere. Edward Bryant took a "sabbatical" from SF a few years ago and has been producing world-class horror ever since. Kurt Vonnegut and Ursula K. LeGuin "graduated" from SF to mainstream acceptance. (To Vonnegut's credit for honesty if nothing else, he allows as to how he gets nostalgic every once in a while, opens the lowest desk drawer where he keeps his old pulp SF efforts, and then urinates into it.) Doris Lessing, Margaret Atwood and others write their most memorable fiction in SF, but they deny any association with the field. Neither lady mentions urinating into desk drawers, but one suspects that they would feel a certain pressure on their respective bladders if forced to accept a Hugo or Nebula.