Pragmatic ethics is a theory of normative philosophical ethics. Ethical pragmatists such as John Dewey believe that some societies have progressed morally in much the way they have attained progress in science. Scientists can pursue inquiry into the truth of a hypothesis and accept the hypothesis, in the sense that they act as though the hypothesis were true; nonetheless, they think that future generations can advance science, and thus future generations can refine or replace (at least some of) their accepted hypotheses. Similarly, ethical pragmatists think that norms, principles, and moral criteria are likely to be improved as a result of inquiry.
Much as it is appropriate for scientists to act as though a hypothesis were true despite expecting future inquiry to supplant it, ethical pragmatists acknowledge that it can be appropriate to practice a variety of other normative approaches (e.g. consequentialism, deontological ethics, and virtue ethics), yet acknowledge the need for mechanisms which allow society to advance beyond such approaches, a freedom for discourse which does not take any such theory as assumed. Thus, aimed at social innovation, the practice of pragmatic ethics supplements the practice of other normative approaches with what John Stuart Mill called "experiments of living".
Establishing that this normative theory entails pragmatism (or vice versa) remains an open challenge. The Blackwell Guide to Ethical Theory refers to this theory as pragmatic and finds it in the writings of John Dewey (a pragmatist). However, it also finds key concepts in the writings of John Stuart Mill and Martha Nussbaum, and we can see at least some of its distinguishing characteristics in the concept of social gadfly attributed to Socrates in Plato's Apology.
Pragmatic ethics has been criticized as conflating descriptive ethics with normative ethics, as describing the way people do make moral judgments rather than the way they should make them. While some ethical pragmatists may have questioned the distinction between normative and descriptive truth, the theory of pragmatic ethics itself does not conflate them any more than science conflates truth about its subject matter with current opinion about it.
Moral ecology is a variation of pragmatic ethics which additionally supposes that morality evolves like an ecosystem, and ethical practice should therefore include strategies analogous to those of ecosystem management (e.g. protecting a degree of moral diversity). The term "moral ecology" has been used since at least 1985 to imply a symbiosis whereby the viability of any existing moral approach would be diminished by the destruction of all alternative approaches. According to Tim Dean, current scientific evidence confirms that humans do take diverse approaches to morality, and such polymorphism gives humanity resilience against a wider range of situations and environments (which makes moral diversity a natural consequence of frequency-dependent selection).