These are lonely times for Lebbeus Woods.

In the early 1990s this irreverent New York architect produced a series of dark and moody renderings that made him a cult figure among students and academics. Foreboding images of bombed-out cities populated by strange, parasitic structures, they seemed to portray a world in a perpetual state of war, one in which the architect’s task was to create safe houses for society’s outcasts.

Since then Mr. Woods has become his own kind of outcast.

Architecture is big business today. While most of his friends and colleagues have abandoned their imaginary cities to chase lucrative commissions, Mr. Woods has shown little interest in building. Instead he continues to work at a small drafting table in a corner of his downtown apartment, a solitary, monklike figure churning out increasingly abstract architectural fantasies, several of which are on view in the “Dreamland” show at the Museum of Modern Art.

Some question the wisdom of his choices. (They certainly haven’t made him a rich man.) But that he now stands virtually alone underscores a disturbing shift in the architectural profession during the past decade or so. By abandoning fantasy for the more pragmatic aspects of building, the profession has lost some of its capacity for self-criticism, not to mention one of its most valuable imaginative tools.