In college, she conned her parents into financing a junior year in Europe by feigning a desire to transfer from the Connecticut College for Women to co-ed University of Pennsylvania to take more art courses. Her parents supposedly thought she’d be more in danger of losing her virginity stateside in the company of male students than in a nominally single-sex art-history program in Paris. Tucker promptly had her first sex—with a Frenchman named Henri, of course—on the boat to Europe. She fell in love and they moved in together in France. Mom and Dad found out and cut off her allowance. The romance ended when Henri was drafted into the French army and killed in the Algerian war. A year or so later, Tucker met a sad-sack theater student named Michael Tucker and married him. One glance at the wedding photo of the couple seated behind the bride-and-groom cake tells you that the union was doomed: Marcia gazes unhappily off to the left, with a shell-shocked Michael by her side.

After her divorce from Michael, Tucker eventually had the good fortune to meet and marry the artist Dean McNeil, 17 years her junior, and to give birth, in her mid-40s, to a daughter, Ruby. But her bad luck returned in her 60s, when she was diagnosed with breast cancer. She underwent a lumpectomy (“which sounded more like a method of getting crabmeat out of the shell than a medical procedure”) and thought she was in the clear until diagnosed with lymphoma. Because of her illnesses, she was compelled to retire from the New Museum earlier than planned, and she seriously considered suicide. Characteristically, she bucked herself up, learned stand-up comedy and performed as an art-world Phyllis Diller under the name of Miss Mannerist. As the end drew near, she wrote one of the most moving last letters to friends and family you’ll ever read. (I won’t quote it here. It must be taken whole.)

Through most of her pre-Whitney life, Tucker wanted to be an artist and combined her grad-school art-history studies (she earned a master’s degree from NYU) with as much painting as she could cram into her overstuffed schedule. Inevitably, though, she had an epiphany: “I realized that I would rather be locked up in the library all weekend than spend a single afternoon facing an empty canvas.” A more radical form of that bookishness marked Tucker’s style as a curator. She was fascinated not so much by how art looked as by the envelope-pushing gestures it could make. In the Whitney’s famous 1969 “Anti- Illusion: Procedures/Materials” exhibition, what “really interested” Tucker were “blocks of ice and leaves; 16-foot-high piles of hay; 40-foot-long liquid ‘pours’ of latex paint; films that had no beginning, middle or end; an empty room whose hidden audiotape whispered, ‘Get out of the room, get out of my mind.’ ” Her favorite creator was Tehching Hsieh, the “vow artist” who lived for an entire year tethered at the wrist by a four-foot rope to another artist, Linda Montano.

Tucker was also an ardent feminist. At the Whitney, her protests that she’d worked much harder than fellow curator James Monte and yet earned less got her equal pay. She joined the activist group Redstockings and was rumored to be one of the Guerrilla Girls, those masked scourges of the male-dominated art world. Not for nothing did she earn the nickname Marching Tucker. “Although we’ve had our differences from time to time,” Tucker writes about the women’s movement, “for over 35 years it’s never once lied, stolen or cheated on me.”

In 1977 the Whitney’s director, Tom Armstrong, let her go in a rather shabby way. When Tucker was offered the dean’s job at the cutting-edge Los Angeles art school CalArts, she asked Armstrong whether he wanted her to stay or go. Stay, he said. After she had said no to CalArts, Armstrong informed Tucker that the museum was reemphasizing the permanent collection and no longer needed an exhibitions-oriented curator. The poor reception of her unengaging Tuttle exhibition was a factor in his decision. She refused to resign, insisted on being publicly fired and then started her own museum. (Little-known fact: In the beginning, all employees of the New Museum, from custodian to director, were paid the same salary—$12,000 per year—and duties were periodically rotated.)