We have here a man of the highest sensibility, of considerable intellect and controlled sexuality, whose libido never outgrew the love-object of the Oedipal phase. . . ."" So writes Hildesheimer of the imaginary Sir Andrew Marbot (1801-1831), the subject of this fictional ""biographical sketch""--an essay/portrait that gives equal emphasis to Marbot's groundbreaking art criticism (he was ""the first to show the way towards psychoanalytically-oriented aesthetics"") and to his incestuous love-affair with his mother. Hildesheimer, whose psychoanalytically-oriented Mozart biography emphasized repression, takes the same approach to pessimistic, remote Marbot--whose admiration of art was colored by the frustration of not being himself an artist: ""We must therefore see his life to some extent as a permanent act of repression, and his suicide. . . as the consequence of an inevitable and definitive perception of the truth."" There are extensive excerpts from Marbot's supposed writings on Giotto, Blake, Turner (a Ruskin-ish parallel), Delacroix. (""But what lies beneath that delicate skin. . . . Is there perhaps some stratum of the artist hidden there which he conceals in life? An unacknowledged yearning. . . .?"") Hildesheimer-the-biographer, while saluting Marbot's pioneering work, expresses reservations about ""this one-sided approach. . . he did now and again sacrifice other criteria in his effort to penetrate the psyche."" And there is intense speculation about Marbot's sexual relationship with his mother--two separate incestuous interludes, guilt, eventual renunciation--as well as his tetchy acquaintanceships with Goe-the (an affair with his daughter-in-law) and other period luminaries. In sum: less an historical novel or a scholarship-parody than an imaginative essay on aesthetics--with offbeat appeal for those seriously interested in psychoanalytic approaches (here, as in Mozart, somewhat blurrily handled) to art-criticism and critical biography.