As a general category of ethical or moral theories, consequentialism refers to theories that evaluate rightness or wrongness based exclusively on the consequences or effects of an act or acts. Consequentialist theories may differ over what kinds of consequences matter, while agreeing that the rightness or wrongness of actions cannot be based on motives or intentions of those who act, nor on the conformity of the act to duty, virtue, piety, moral rules, or the law. Consequences are all that matter for ethics, on this view. According to consequentialists, some murders might turn out to be morally right, while some acts of sincere generosity might be wrong.

Consequentialism is the ethical theory most compatible with the empirical and quantitative focus of much of science and technology. When a consequentialist studies ethical issues in science and technology, an act is usually understood broadly to include national and local policies...