Daniel Callahan (born 1930) was a philosopher widely recognized for his innovative studies in biomedical ethics. The co-founder of the Hastings Center, an internationally-acclaimed research institute for biomedical ethics, Callahan was best known for proposing that a looming crisis in health care resources would require society to set priorities and limits on medical care.

Daniel Callahan was born in Washington, D.C., on July 19, 1930. As a youth he was afflicted with a variety of maladies that resulted in several hospital stays. These experiences disposed him to an interest in matters of medicine, although this interest was not fully realized until later in his life.

Callahan's athletic prowess as a swimmer in high school led him to choose Yale University, the nation's best college for competitive swimming in the early 1950s, for his undergraduate education. At Yale he found himself drawn immediately to interdisciplinary studies, and he graduated in 1952 with...