Phi Beta Kappa, Harvard, 1956
Huntington Library Fellowship 1973-74
Melcher Prize for Henry Thoreau: A Life of the Mind, 1986
Forest History Prize for ditto,
Colorado Seminars Prize for ditto
Guggenheim Fellowship, 1990
Boston Public Library ‘Literary Light’ 1990
Melcher Prize for Emerson The Mind on Fire, 1995
Parkman Prize for ditto
Washington Irving Award for Literary Excellence for ditto
Dictionary of Literary Biography Award for a Distinguished Literary
Biography for ditto
National Book Critics Circle Award finalist for ditto
New York Times Book Review Notable book of 1995 for ditto
Winship/Pen New England award finalist for ditto
Special Award in Literature, American Academy of Arts and Letters, 1998
National Humanities Center Fellowship, 1999-2000
Thoreau Society Distinguished Achievement award, 2001
Emerson Society Distinguished achievement award, 2001
Dr. of Humane Letters, Meadville-Lombard Theological School, 2003
Bancroft Prize for William James: In the Maelstrom of American Modernism, 2006
Dr. of Humane Letters, University of Denver 2008
Centennial Medal of the Harvard Graduate School of Arts and Sciences, 2015