Daniel Callahan, a national voice for responsible health and science, who pioneered the field of bioethics, died on July 16, three days before his 89th birthday. In 1969, Callahan cofounded The Hastings Center with Willard Gaylin. Callahan served as the Center’s director from 1969 to 1983, preside...

This year, The Hastings Center will celebrate its 50th anniversary. The Center was first located on the second floor of my house in Hastings-on-Hudson, N.Y., with some overflow paperwork stored at the home of my neighborhood friend and cofounder, Willard Gaylin.