We are gripped by gossip. Curiosity is a tenacious emotion. In her essay on Push Comes to Shove, the autobiography of the choreographer Twyla Tharp, Joan Acocella acknowledges this in an untroubled way. If you want to know what Baryshnikov was like in bed, she advises, look at p. 208 in a bookshop: ‘Tharp gives him better marks than [Gelsey] Kirkland’ in her 1986 autobiography Dancing on my Grave.