David L. Eng is an associate professor of English at University of Pennsylvania, and his specialties include Asian-American literature. He wrote Racial Castration: Managing Masculinity in Asian America and co-edited Q & A: Queer in Asian America.

David S. Touretzky is a research professor in the computer science department at Carnegie Mellon University in Pittsburgh and a longtime Scientology critic. He maintains an extensive collection of Scientology-related websites on his home page. He has given many radio interviews and appeared on Countdown with Keith Olbermann (twice) and CNN Headline News with Glenn Beck to discuss Scientology.

John Iceland is professor of sociology and demography at Penn State University. He is the author of Poverty in America: A Handbook and has authored numerous papers and reports on poverty patterns, causes and measurement.

Sister Joan Chittister, a Benedictine nun, lecturer and writer, has been especially active on peace issues. She was a guest on an April 16 Meet the Press panel about faith and politics.

Operation Safety Net is a health care outreach program operated through the Pittsburgh Mercy Hospital System and Catholic Health East. It provides medical care to homeless people living on the streets of Pittsburgh and recognized as one of nation’s first, targeted, full-time street medicine programs. Dr. Jim Withers started the program in 1992.

Allen Guelzo wrote Abraham Lincoln: Redeemer President, a 1999 book that challenged the reigning thought about Lincoln’s faith – basically, that he had little, if any. He is a professor of Civil War era history at Gettysburg College.

James Serpell is a professor of humane ethics and animal welfare at the University of Pennsylvania’s school of veterinary medicine. He directs the Center for the Interaction of Animals and Society.

Andrew Isenberg is a history professor at Temple University in Philadelphia. He is an expert on the history of American environmentalism, especially in the American West. He contributed a chapter on the moral ecology of wildlife to the book Representing Animals.

Kerry Walters is a philosophy professor at Gettysburg College in Gettysburg, Pa. With Lisa Portmess, she co-authored two books, one about the history of religious vegetarianism and the other on the history of ethical vegetarianism.