David Callahan is an American writer and editor. He is the founder and editor of Inside Philanthropy, a digital media site, and Blue Tent Daily, which offers in-depth reporting on progressive organizations and the Democratic Party. Previously, he was a senior fellow at Demos, a public policy group based in New York City that he co-founded in 1999. He is also an author and lecturer. He is best known as the author of the books The Givers and The Cheating Culture.

Daniel John Callahan was an American philosopher who played a leading role in developing the field of biomedical ethics as co-founder of The Hastings Center, the world's first bioethics research institute. He served as the Director of The Hastings Center from 1969 to 1983, president from 1984 to 1996, and president emeritus from 1996 to 2019. He was the author or editor of 47 books.