This monumental 656-page biography is probably the fullest, most revealing account to date of Tchaikovsky's private life. Poznansky identifies the death of the composer's mother as a shattering experience for young Pyotr Ilyich, a source of deep existential melancholy. His hypersensitivity, forged by a child's feeling of paradise lost, would manifest in neurosis, insomnia and depressive fits marked by "a sense of insurmountable terror. " A Yale University librarian, Poznansky explores the composer's obsessive fear of death, his idealized relationship with eccentric, free-thinking patron Nadezhda von Meck, the fiasco of his brief, unconsummated marriage, and his involvement in a homosexual subculture that simultaneously fascinated and repelled him. Drawing on Russian sources, the author refutes the theory that Tchaikovsky's death in 1893 at age 53 was a suicide forced upon him by a conspiracy of former classmates. "The story of a soul finding itself," this remarkable book casts only an indirect light on the relationship between Tchaikovsky's life and art, as the author omits extended discussion of the music. Photos.