Outsider artists often present a pathetic spectacle to the world: forgotten inmates of mental institutions; shuffling, muttering loners; or misfits, like Henry Darger, who spent his workdays as a low-paid janitor and his free time writing and illustrating an unpublishable 15,145-page novel about a vast planet where the evil nation of Glandelinia conducts cruel wars of enslavement against the good children of Angelinia.

Some of the fruits of the lonely furrow Darger plowed are now on display at Tokyo's Hara Museum of Art. Like many of his ilk, Darger, who was born in 1892, was institutionalized for part of his life and died in impoverished anonymity. He never benefited from artistic training, lacked confidence in his art, and never willingly showed it to anyone. His work was rescued from oblivion by his landlord, Nathan Lerner, a commercial artist who discovered it when terminal illness forced Darger to move to a hospice in 1973.

These circumstances might suggest that his art is collected because of a patronizing sense of pity. But, to an art world that craves originality, outsider art has one advantage over art produced by artists connected to the art world -- uniqueness. Along with aesthetic merit and craftsmanship, uniqueness is part of the basic currency of art. It invokes scarcity, and scarcity creates value. With smaller pieces selling for over $25,000, Darger's works have acquired a reputation for being like nothing else.