A contributing editor to UU World until his death in 2002, Simmons was an associate professor of English at Lake Forest College in Illinois. Diagnosed at age 35 with ALS (Lou Gehrig's disease), Simmons moved to New Hampshire with his wife and two young children and wrote a series of essays about what he called "the blessings of the imperfect life."
His essays are collected in Learning to Fall: The Blessings of an Imperfect Life (Bantam, 2002). His novel, Rattlesnake Ridge (Wasteland, 2004), was published posthumously. A documentary film recorded during the final months of his life, The Man Who Learned to Fall, was released on DVD in 2004.