John Baird Callicott is an American environmental philosopher.  He pioneered the field now known as environmental ethics.

Callicott was born in Memphis, Tennessee in 1941.  He attended Syracuse University, from which he received a Ph.D. in philosophy in 1971.  After teaching at numerous universities, he became a Professor of Philosophy at the University of Wisconsin-Stevens Point, where he taught America's first college-level course in environmental ethics.

Callicott has done extensive research on American ecologist Aldo Leopold.  Callicott has extended Leopold's land ethic into modern times, applying it to various contemporary environmental scenarios.  He has also authored Companion to A Sand Almanac, which provides a critical discussion of Leopold's work.  In 1989, Callicott put together a collection of essays entitled In Defense of the Land Ethic, a volume that examines the basis of Leopold's beliefs.  In 1991, Callicott helped publish Leopold's final unpublished works under the title The River of the Mother of God and Other Essays.

Callicott has produced numerous other writings as well.  He has written a number of articles for philosophical, technical, and scientific anthologies, and he has contributed to over twenty books.  He is also a renowned public speaker.

Callicott advocates protecting and improving the environment through cautious environmental management and the use of flawless information about the environment.  His theories are still not widely agreed with, but they are thought to have the potential to radically change future environmental thinking and practice.

Intrinsic Value in Nature: a Metaethical Analysis