Anish Kapoor can demand quite a lot from his audience. For some, gazing into dark whirlpools, into the blackest of black, may be unsettling, depending on one's state of mind. Added to that is dark red wax, one of his favorite materials: It symbolizes flesh and blood. Associations that cut straight to the core. And yet, the artist seems cheerful and relaxed talking about his work. At times, however, it makes even him feel a little uneasy. Take, for example, the major exhibition of his work