Thaw opened an art gallery and bookstore on West 44th Street at the
Algonquin Hotel in 1950. He moved the gallery to
Madison Avenue in 1954, and he served as its president from 1970 to 1972. and the
Morgan Library & Museum. Thaw was also an art collector. Thaw's collection included drawings from modern and old masters, American Indian art, ancient Eurasian bronzes, early medieval jewelry, Native American art, architectural models, and eighteenth- and nineteenth-century oil sketches, French faience, in addition to paintings, sculpture, and furniture. He was the owner of drawings and paintings by
Paul Cézanne,
Joseph Cornell,
Salvador Dalí,
Honoré Daumier,
Edgar Degas,
Eugène Delacroix,
Jean-Honoré Fragonard,
Alberto Giacometti,
Vincent van Gogh,
Francisco Goya,
Lee Krasner,
Georgia O'Keeffe,
Pablo Picasso, and
Jackson Pollock,
Odilon Redon,
Rembrandt, as well as
Native American art. In 2008, The
Cooper Hewitt National Design Museum held an exhibition titled "House Proud", that commemorated a substantial gift made by Eugene and Clare Thaw of eighty five nineteenth-century exquisitely detailed watercolors of domestic interiors, the largest collection of this subject matter in America. The selection was ultimately shown in Paris at
Musée de la Vie romantique in 2012-2013.
The Morgan Library & Museum published a collection of his articles as
Reflections of an Independent Mind in 1997. The book predominantly contains
book reviews from 1980 to 1995 (including a very negative review of
Suzi Gablik's
Has Modernism Failed?), but also articles on collecting (1977-1995), museums and auction houses (1977-1990), and essays on Vincent Van Gogh (1980, 1984), Paul Cézanne (1984), Edgar Degas (1985),
John Cheever (1982),
Ralph F. Colin (1985),
Pierre Matisse (1989),
János Scholz (1993, 1995),
John Rewald (1994), and
Lore Heinemann (1997). These articles originally appeared in periodicals such as
The New Republic,
The New York Review of Books,
The New York Times Book Review,
The Times,
The Spectator,
The New Criterion,
Heritage,
ARTnews, and
The American Scholar, as well as book editions of art works in his collection. ==Personal life and death==